Rich Dlin – Reader Beware

Husband, Father, Math Teacher, Weightlifter

Archive for the category “Math”

Open-Mindedness

Recently I have been thinking a lot about why so many people seem inconvincible of certain things which I hold to be true. And while I could certainly make a list of some of these things, that is not the intention of this blog entry. Instead, I have been reflecting on open-mindedness and wanted to share.

Many people – myself included – often enter into discourse with someone of a differing opinion with the intention of convincing them to change their mind. For example, maybe your friend Paul thinks all trees in your neighborhood that are taller than 12 feet should be pruned to 12 feet or less, so as not to obstruct anyone’s view of the lakefront. You know that he’s clearly wrong! You get into a discussion. Only it’s not really a discussion – it’s an argument each of you is trying to win. Maybe out of frustration you start incorporating personal attacks. Maybe you get so angry at Paul’s refusal to capitulate, as well as the horrible things he is saying about you, that it ends your friendship. Maybe in the middle of the night, Paul prunes all of your tall trees. Maybe the next night you erect a 30 foot statue on your lawn directly in Paul’s line of sight to the lake … and so on.

It’s sad, and you don’t even like the statue, but what choice is there? Paul must be taught a lesson.

I wish this was hyperbole. Sadly, it is not. And the conclusion is clearly suboptimal.

Well … let me construct a basis for discussion with some (hopefully) fair assumptions. In doing so I’m going to have to use a little bit of math terminology, and it occurs to me that some people might not know precisely what I mean, or even be put-off by some of my more mathematical references. If you think this might be the case, I ask you to bear with me. The concepts and symbols I use are the best way for me to illustrate my point, and I’ve included here a bit of a math lesson, in case it is not something you’ve encountered in your life – it will clarify some of the words and concepts I use for the rest of this article. Of course, if you feel there’s no need for you to read this section, by all means scroll past it and keep reading (I won’t feel bad).


Some Math concepts

Sets
Mathematicians like to talk about collections of values that are somehow related, and when they do, they use the word set. We use curly brackets to list the objects (known as elements) of a set. So for example the set F=\{apple, orange, banana, kiwi, peach, nectarine\} is a set I have named F, and just so you know, it is the set containing all the fruits I might bring to work with me in my lunch. A subset of a set S is another set that only contains elements from S. So for example M=\{apple, kiwi\} is the set of fruits I brought to work in my lunch on Monday, and is a subset of F. On the other hand, A=\{apple, pineapple, banana\} is not a subset of F.

A Little Bit of Algebra (Apologies to the Arithmophobic)
Consider this simple algebra equation:
\displaystyle 3x+4y=7
The x and y are understood to be symbolic of numbers, but the use of symbols mean that they vary – which is to say, they are variable. The equation is a statement. In this particular statement,
x = 1, y=1
would be a valid solution (i.e., the equation becomes true), since
3\times 1 + 4\times 1=7.
So would
x = 5, y=-2,
since
3\times 5 + 4\times (-2)=7.
However
x = 5, y=2
would not be a solution (i.e., the equation becomes false), since
3\times 5 + 4\times 2=23,
which is not 7.

Statements
In math and philosophy, a statement is a sentence that must either be true or false (but not both, and not maybe). Very often the truth value (i.e., “true” or “false”) of the statement depends on values for variables contained in the statement. The algebra equation above is a statement. Another example is the statement “I like cheese”, which contains two variables: “I”, and “cheese”. If the “I” refers to “Rich Dlin” (i.e., it is me speaking and not you), and the “cheese” refers to “Havarti”, then the statement is true. If the “I” is “Rich Dlin”, and the “cheese” is “Cambozola”, the statement (I promise you) is false. Notice that if the “cheese” were to refer to “gingerbread cookie” the statement would be nonsense, since “gingerbread cookie” is not a cheese – even though it is true that I like gingerbread cookies, it is irrelevant in the context of this statement. A mathematician would say “gingerbread cookie” is not an element of the set of all cheeses. Going back to the algebra example, {(1,1),(3,-2)} is a subset of the set of solutions to the equation given. The actual set has an infinite number of solutions in it, but that’s more than I need to talk about here. What I will say is that the truth value of the statement “Three times John’s favorite number plus four times Gail’s favorite number will yield seven” is:

True if (“John’s favorite number“, “Gail’s favorite number“) belongs to the set of solutions of 3x + 4y = 7,

False if (“John’s favorite number“, “Gail’s favorite number“) does not belong to the set of solutions of 3x + 4y = 7, and

Nonsense if, for example, John claims his favorite number is “cinnamon“. Be on the lookout for nonsense – it is surprisingly common.



The Assumptions

Ok. Welcome back. Here are the assumptions I was talking about:

All questions have a right answer
… when the answer is justified properly with a well framed statement.
The truth value of the statement may be subject to variables that change which answer is correct, but with a fixed set of values for the variables, there is a right answer. For example, the question “Should all trees taller than 12 feet in our neighborhood be pruned?” could be answered “Yes”, justified with the statement “It is unacceptable for some trees in our neighborhood to block sight lines to the lakefront”. Note that here the answer to the question is “yes” if the statement is true, and “no” if the statement is false, and may reasonably depend on whether or not the tree is also so wide, or part of a grove, as to make it impossible for a resident to see the lakefront from a different angle standing on the same property. It may also depend on whether 12 feet is a reasonable height with respect to whether or not sight lines get blocked. In this case these variables need to be introduced into the statement, or else agreed upon as not being variable.

The right answer may well not be knowable
 … even with the variable values fixed – which doesn’t mean there is no right answer!
As an example, consider the question “How many humans are alive on Earth right now?”

  • The number changes many times in a short span of time. So the truth value of the answer depends on what time it is indexed to.
  • The answer is subject to a definition of “alive”, and the answers to whether or not some organisms are living humans are in dispute.
  • “On” Earth needs to be defined. If I am in an airplane, am I on Earth? What if I am in low orbit?
  • However there is an answer, if we fix the variables.
  • There is currently no way, even with the variables fixed, to know the answer.

Knowing the truth is inherently valuable.
This is a big one. Many people demonstrate by their behavior that they do not adhere to this assumption. A simple example is the person who refuses to go to the doctor about a problem because they are afraid of what they might find out. In some ways, not wanting to know the truth is a human quality, especially in situations where a false belief has spawned an entire tree of values and beliefs we have been living by. If the root belief is false, what happens to the tree?

When it Comes to Truth, What We Want Doesn’t Matter
So with these assumptions, my position is that for any belief I hold, I am either right or wrong, and that I may not be able to tell. So then what am I to make of someone who disagrees? Can I immediately conclude that they are wrong? Clearly not. However I freely admit I want them to be wrong, so that I don’t have to be. After all, being wrong has some negative implications. On a fairly benign end it means I have been somehow deluded, which injures my pride. On an extreme end it may mean I have to discard an entire tree of conclusions that were premised on my error, leaving behind a buzzing hive of uncomfortable questions and observations about my previous behavior. But if the root belief is actually wrong, what choice do I really have? Since it is rooted in falsehood, the whole tree is an illusion anyway.

Here is a hard truth: What we want has nothing to do with what is true. I want there to be peace in the Middle East. But there is not peace in the Middle East, and no amount of wishing on my part, no matter how fervent, can alter the truth value of this or any other statement. On the other hand, what is true can and should definitely impact what I want. What we all want.

Ok. Here is another statement that is tautologically true: In the set of things I hold to be true, some might be false. And from a probability perspective, I am also comfortable saying that in the set of things I hold to be true, some are true, and some are false. I want to say “most are true and some are false”, but I am honestly not sure I have a reasonable argument to claim that, so we’ll leave it there as a desire more than a fact.

Shades of Gray
Now I will focus on statements where the truth depends on fixing values for the variables in the statement., which to me is the core of the shades of gray argument: In cases where there is a continuum of possibilities between true and false, almost everything in the set of things I hold to be true lies somewhere within the boundaries of the continuum, rather than on one of the ends.

Here a philosopher or mathematician might (and should!) argue that there can be no continuum between true and false, since those are binary options. My response is that I am talking about a sphere of reasonable answers centered on the truth, where anything outside the sphere is easily demonstrated to be false (or worse, nonsense), but things get a little more touchy inside the sphere. This is a consequence of my point about the truth of a statement depending on fixing values for variables the statement depends upon. To elaborate on this, I am going to define something called an assumption set.

Assumption Set
Suppose a statement depends on a set of variables. For example, consider the statement “Running is good for you.” The truth of this is not absolute. It depends on some variables:

  • How much running (the quantity of the running)?
  • How intense (the quality of the running)?
  • What preconditions do you have that running would exacerbate (e.g, bad knees, asthma, heart problems)?
  • Where do you plan to do your running (road, track, beach)?
  • and many more.

So before we could discuss whether the statement is true, we would have to fix values for these variables. I call these fixed values the assumption set. So for example an assumption set for this statement could be
R=\{45 minutes per day, at 80\% of maximum heart rate, \{sensitive to sunlight, plantar fasciitis\}, track\}.
Notice that one of the elements (the preconditions) in this assumption set is itself a set – that’s completely acceptable. On the whole, I would judge this assumption set to be a reasonable one – which is to say, the elements of the set have a probability associated with them that makes them not unexpected in the context of discussing the claim that “Running is good for you.”
Another assumption set could be
S=\{15 hours per day, at 120\% of maximum heart rate, \{multiple hip replacements, torn Achilles tendon\}, Interstate Highways\}.
On the whole, I would judge this assumption set to be very unreasonable – which is to say, it is highly improbable that this would be an assumption set on which the claim “Running is good for you” would be a relevant discussion.

Reasonable Answers (Approximately True?)
A reasonable answer to a question can be defined as a statement that is true when evaluated with a plausible assumption set. That is to say, the assumption set is comprised of elements that have probabilities high enough that if we observed them we would not be surprised. In situations where the variables are in constant flux, the approximate truth value of a statement may be argued as the one that holds given the most likely assumption set. In cases like this, we may generalize a statement as true, while being willing to challenge it in the face of a game-changing assumption set. We maybe won’t talk about who gets to define “plausible”, even though there are times when that becomes the most relevant thing.

Arguing(?) With an Open Mind
Here I have chosen to use the word “arguing”, even though in truth I prefer the word “discussing”. That’s because most people seem to think that discussions between people in disagreement need to be arguments. I disagree. Remember the assumption that we are not right about everything? And remember the assumption that knowing the truth is inherently valuable? These two should premise every discussion we enter into. So when discussing the answers to questions, or the truth about statements, we need to do our best to remember that what we are trying to do is get as close to the center of the sphere as possible, because that is a good thing to do, and because we may not be there yet.

Of course, we all think we are closer than an opponent. If not, we wouldn’t be having the discussion in the first place. But keeping in mind that if two people are in disagreement, one of them must be wrong, a productive conversation is one where at the end of it the parties have converged on something they both hold to be as close to true as they can see getting. When this happens, the world gets a win. I’ll list some techniques for true open-mindedness.

Discussing With an Open Mind

  1. Remember that you might be wrong.
    Put another way, be willing to change your mind, or adjust the approximate truth of what you believe.
    See, you believe that you are probably right. You may even believe that you are certainly right (although for the truly reflective, certainty is a pretty difficult thing to attain). But your opponent has the same thoughts. Both of you probably have many reasons for these. And they probably have a lot to do with assumption sets, and which one of you is applying the most plausible set. Sometimes the discussion is not about the truth of the statement but on the plausibility of the assumption set. Keep that in mind. Yours may be the less plausible. Or maybe both assumption sets are equally plausible, in which case the statement can be split into two (or more) more detailed statements that include some of the differing assumptions explicitly. But keep in mind that emotional attachment to an assumption set can and will blind you to the plausibility of an alternate set, and ultimately cause you to refute a statement with unreasonable (even fanatical) obstinacy.
  2. Have higher expectations for yourself than you do for your opponent.
    This means you need to challenge yourself to inspect the assumptions and claims of yourself and your opponent objectively, even if they are not doing the same thing. When you do this – and do it out loud – they hear that. Look at elements of the assumption sets and objectively evaluate their probability. Also evaluate whether they change the truth value of the statement or not. And be prepared to evaluate whether or not they render the statement as nonsense – this happens surprisingly often but it’s not obvious until it is isolated. Discussing things this way models a behavior that is necessary for the two of you to converge on a conclusion you both agree with. And if you are consistent with it, your opponent will often adopt the same style, if only because they think this is the way to convince you they are right.
  3. Thank your opponent, regardless of the outcome.
    I don’t mean this as a politeness. I mean this in the most sincere sense. Any opportunity we get to reflect on our set of beliefs is valuable. Sometimes your opponent and you will converge. Sometimes you will not, and they leave the exchange completely unmoved, perhaps even claiming “victory”. This is sad, since the only true victory would be a convergence of opinion, but ultimately it is not relevant to your own experience. Make it so that if you have moved on a topic, it is because you discovered something you were not considering, or were considering incorrectly, and now you are closer to the center of the sphere of truth. If you do not move, make it because you were not presented with any strong evidence that you needed to. In either case your beliefs will have been strengthened in some way, either because you changed to something as a result of new insight, or because you were challenged in some way, and it was unsuccessful. For this you have your opponent to thank.

How to Spot Real Open-Mindedness
Many people claim to be open-minded. It may be true, or it may be a trick (some people say it so that when you fail to convince them of something it will prove they were right). True open-mindedness doesn’t mean you are ready to believe anything. It means you are willing to change your mind when presented with evidence that objectively compels you to do so. If you know of (or are) someone who has changed their mind in the moment, during rational discourse, but who was fairly slow to do so, they are probably the type of person I am describing. This goes back to my point that we are probably not right about everything we believe. Which means mind-changing can occur. Which means if you’ve seen it occur, it occurred in someone with an open mind.

Thanks for reading,

Rich

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Our Schooling System is Broken

It has been a while since my last blog – it was never my intention to go so long between posts but you know … sometimes life hands you other things. In any case I plan to start writing again more frequently, starting with a subject that has been on my mind for a while now: Education.

See, I am thinking our system might be broken. Scratch that – I know it’s broken, and in many ways. But I am talking about a fundamental issue, which is the assumption that performance in a school system with a standardized curriculum is a key measure of personal value. I will try to explain, starting with some background for context.

I Am a Teacher

It’s true. I am a teacher. A very happy one at that. I love my job. I teach high school math in Ontario, Canada, and have been doing that for about 15 years. Prior to that I worked as a software developer for about 10 years. When people ask me what I do for a living (something other adults seem to have a deep need to know upon meeting each other), the conversation always goes roughly the same way:

Other Adult: “So Rich, what do you do for a living?”
Rich: “I’m a teacher.”
OA: “Oh? Nice. What do you teach?”
(Rich’s note: There may or may not be a “joke” here by OA along the lines of “Oh yeah? You know what they say: ‘Those who can, do, and those who can’t, teach’ hahahahaha”)
Rich (being honest, even though it’s not what they meant): “Kids.”
OA: “Oh, haha. But seriously, what subject?”
Rich (with an inward eye-roll – here it comes): “I teach high school math.”
OA: “Oh god. I hate math. I remember I used to be so good at it until grade 8 when I had Ms. Heffernan. She hated me! And she was so terrible to the kids. She made me hate math. I never understood anything in math after that. I am so bad at math! The other day I tried to help my 7 year-old with her homework and I couldn’t even understand what they were doing. Do you tutor? I think I may need to hire you to help little Kelly with her math. Math is so confusing. I keep telling her she doesn’t need it anyway. I mean, I run a multi-million dollar business and I never use any of the math they tried to teach me in high school. Why don’t you guys start teaching useful stuff like understanding financial statements and investing? I had to learn all that stuff on my own. I don’t see why math is so important. I am really successful and I was never any good at it thanks to Ms. Heffernan …..”
Rich: “I apologize on behalf of all my brethren. Please carry on with your successful math-free life. Yes, I’d be happy to help Kelly, but honestly she probably doesn’t need any help. She’s 7. She will conquer.”

You get the point. But as I said, I seriously love my job. For many reasons. But perhaps the main one is that it keeps me connected to the fluidity of humanity. I keep getting older, but my students do not. They are the same age every year. And because I spend a large number of hours each day immersed in their culture, it forces me to keep my thinking current, so that I can continue to effectively communicate. In this way I feel less like some sort of flotsam floating on the river of time and more like a beaver dam of sorts, constantly filtering new water on it’s way downstream, being shored up with new materials as each generation passes through. I am like a connection between the past and the future, and the older I get, the larger the gap I am privileged to span. And in any case, young people are perpetually awesome. It brings a faith in humanity I’m not sure I could get in other ways to see firsthand the caretakers of the future.

School Is Not Really About Education

I can hear your thoughts.

Um, what? Isn’t school by definition about education?

Well, yeah. Granted it’s supposed to be. But it isn’t. All you have to do is talk to almost any adult existing in Western society today about it and they will tell you (often with great relish, as though they are solving world hunger), they never use a single thing they learned in school in their day-to-day lives. Which is of course false. But mostly true. If you went to school in Canada you probably at some point had to know things like what year Champlain landed in Quebec (1608, in case you’re stumped – I just Googled it). I can say with a fair amount of confidence that whether or not you have that tidbit of info available in your memory banks is not affecting your life in any measurable way. You probably also had to know the quadratic formula at some point. I don’t have to Google that one. It’s x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}. Nifty, isn’t it? Sorry if I scared you.

Here. Check out these definitions of “education”. I Googled it.

Definition of Education
Side note: Google is so cool. I’m 48. I have existed both with and without Google. I had to assimilate the use of Google as a verb into a lexicon that did not previously have it established that way. Your kids didn’t. They have to establish the word googol as a noun referring to the number 10^{100} into a lexicon that likely does not have it established that way.

See? The very first definition says I am wrong. School is about education, literally by definition. Oh, but check out definition number 2! Now that is a good one. Education is an enlightening experience! The thing is, in many cases, and for many people, school isn’t enlightening. In many cases, school is an exercise in conformity and alignment. It’s a system which simultaneously (and somewhat arbitrarily) defines success (um, I think I mean worth) and then provides measures for individuals to evaluate their success (yeah, I definitely mean worth).

Performance of Curriculum is a False Measure of Worth

Ok. So when you were a kid, around the age of 5, your parents sent you off to school. And almost immediately, you started to get report cards. They aren’t cards anymore. In many cases they aren’t even paper. But still called report cards. A figurative card summarizing your score on a number of predetermined criteria for success. And make no mistake – from that very first report card on, kids are sent the message that they must perform according to standards so that they get good report cards. I’m going to stay away from the early years, since that’s not my area of expertise, and fast forward to high school, which is. Let’s look at an example. This is based on a real person, whose name I’ve changed. Yes it’s anecdotal. It’s not meant as proof, only to demonstrate my point.

Sally is a young lady in grade 9 who has never particularly had an interest in math – at least in how it’s presented at school. She really doesn’t care about direct vs. partial variation, or the sum of the exterior angles of a polygon, or about how doubling the radius affects the volume of a sphere. But Sally goes to school, in a system which has not only determined that these things are important, they are also mandatory. So she has no choice but to engage in attempts to learn about these things, despite the fact that she is actually incapable of being interested in them. Sally is awesome, by the way. A genuinely caring human with deep empathy, intense loyalty, and a great sense of humour. Sally is also depressed, because she feels worthless. No matter how hard she tries, she can’t figure out how substituting 2r for r into the formula V=\frac{4}{3}\pi r^3 causes the volume to increase by a factor of 8. In a test designed to determine if Sally can do these things, her performance was dismal. Her mark on that test was a 58%. The class average was 85%. When the teacher returned the test, she made comments like “Well, I know that I taught about exterior angles, but it is clear that some of you did not learn it.” When Sally brought the test home to show her parents (who, incidentally, knew that Sally had the test coming up, hired a tutor to help her prepare, and then asked if she had gotten it back each day after school starting the day after it had been written until the day a week later when it was returned), her parents were frustrated and disappointed. Sally has been conditioned to believe that her ability to understand direct and partial variation is critical. Because it is mandatory, her inability to care or comprehend is forcibly highlighted. And subsequently, her performance is recorded for posterity on her report card. Sally’s final grade in math ends up being 61%. Her parents are disappointed. Sally is devastated. She believes there is something fundamentally wrong with her, because she legitimately can not measure up to the standards set in a system she has no choice but to be engaged in.

Breaking Down the Process

Let’s have a look at this situation of Sally’s, and the number of places where the system went wrong.

First off, the concepts Sally has to learn have honestly been arbitrarily determined. See, someone, somewhere, decided that Calculus is an important prerequisite subject for many university and college programs. And to learn Calculus (a grade 12 subject in Ontario), you arguably have to start with concepts like direct and partial variation in earlier grades. And because grade 9 is truly too early to know if programs that require Calculus are in your future, this pre-calculus material is incorporated into the curriculum for pretty much everybody.

Second, math is mandatory. In Ontario high school is a 4-year program, and you must have a minimum of 3 math credits to earn a high school diploma. All of this has nothing – and everything – to do with Sally. Next comes the process. Sally’s teacher created quite possibly an amazing series of lessons on these topics. Sally just doesn’t have the wiring for them, so even though the teacher may be phenomenal, it will have a marginal impact on Sally’s ability to synthesize the material. Sally used to ask questions in class. Now she doesn’t, because she learned that even when she asked, it didn’t help. Sally is deeply empathic – she has seen firsthand the good intentions and effort of her teachers in the past. She can read facial expressions and body language. She has seen her teachers answer her questions and try to help her and seen how much they believe the answers and help are working, so she has pretended that it was, since that was easier than admitting that it wasn’t, because it meant burdening herself with her inadequacy instead of her teachers.

Third, Sally has been conditioned to believe that it is all being done so that she can get high grades. Because ultimately her success is defined by her report card. And because pretty much everyone is telling her that you don’t need this stuff in life anyway. You just need to learn it to get high grades so you can be successful. Which means the only purpose to learning this stuff is the test you will eventually write on it. This is exacerbated by the well-intentioned parents who put so much emphasis on the test – both before and after. You’ve heard the question “When am I ever going to use this?” Well the answer for most kids is “Next week, when you are tested on it.”

See? It’s all artificial. Sally is a high-worth kid, forced into a situation she isn’t wired for, and told that her worth is defined by her performance in that situation. It’s incredibly sad to watch.

The Present and the Future

So here’s where we are now. Many kids and parents these day believe that high marks are critical. The perception is that material presented in school is not inherently valuable, but instead the value is that it is a vehicle to high marks. This means that kids will often do anything it takes to get the high marks. This includes cheating, but that’s not really what I am driving at. What I mean is that they develop strategies that focus on getting high marks, as opposed to learning. Cramming for tests, paying for courses in small private schools that guarantee (implicitly or explicitly) very high grades, or negotiating with teachers (even to the extent of aggressively bullying) after the fact are all standard operating procedure. What is so terrible is that Sally may be able to get high grades using any of these tactics. But Sally will also always know that she didn’t earn them. She will always know that she is not good at something that she should be good at if she is to be valuable. And if and when she manages to gets the high grades anyway, that sense of fraudulence will haunt her. I’ve seen it. It’s tragic. Sally has a great future if she can discover her true worth. The worth she was born with and the worth that her friends probably value more than anything she can do in a math class. But she may or may not discover it.

What I Do About It

I love people. And that includes the kids I teach. And I teach high level math, which is honestly not for everyone. I get a lot of kids coming through my classroom doors who are not there because they want to be, and who will not be able to draw the joy from studying math that I really, really do. I have constraints. I have to teach the material as it’s laid out by governmental process. I have to assign grades that reflect students’ performance against some pretty specific criteria. But within this I make sure that each and every kid I teach knows that I value them as a person. That I care about their story. That I see them not as a 2-dimensional projection of my consciousness, but as a multi-dimensional consciousness of their own, with a narrative as rich and intricate as mine. I make sure that they understand that any evaluation I do of their abilities in math is a tiny, tiny cog in the complex machinery of their existence, and has zero impact on my impressions of them as people, or on my estimation of their worth. I show them that it is totally acceptable to love and be passionate about math, without tying that love and passion to an evaluation. It’s not about the math. It’s about giving them permission to take joy out of abstractions, and to pursue the things that they were wired to do. I’m not always successful. Some kids are too preconditioned. But I will never stop trying.

Thanks for reading,

Rich

Thoughts From a Dance Dad

Lately it seems as though the amount of time I have to write is inversely proportional to the amount of ideas I have to write about. But today’s entry is about something I’ve been thinking about for years: Dance.

Early Years

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My Little Ballerina (age 5)

My daughter is a competitive dancer. She’s 15, and has been dancing since she was around 3. She’s gone to countless dance camps, workshops, and of course classes. So I have been a dance spectator for about 12 years. Prior to that I knew next to nothing about dance, save for the fact that I have never been any good at it.

At first, dance was pretty much entirely about how cute the kids all looked executing choreography. They got to wear these elaborate costumes and perform for friends and family at recitals. The teachers and teaching assistants are always on stage at the same time as the kids, and the kids essentially never take their eyes off them, mimicking the movements they’ve all spent months in class learning. It’s exceedingly adorable, and naturally every person who comes to watch immediately rushes to them afterwards to tell them how wonderfully they danced. In short, it’s a typical exercise in getting kids involved in an activity that provides some structure around working toward a goal, and then the kids get congratulated on essentially existing for the duration. And it’s awesome.

As the years progressed, we saw less and less boys involved. I won’t attempt to analyze that or comment on why it might be, but political minefield notwithstanding, it is true. This meant that as the dancers grew, it became – for my daughter’s group at least – a girls-only activity.

Emerging Talents
1042Starting around the age of 8 or 9, and lasting for 3-4 years, it starts to become obvious which of the girls are well suited to dance and which are not. This obviousness is not lost on the girls. Dance becomes a micro-society where “Haves” and “Have-Nots” start to identify, and the behaviours that result are what you would expect. In a way it mirrors what is happening at that age in school, but from where I sat it was definitely magnified at dance. These can be pretty difficult years for the girls, and perhaps more so for the parents. As I watched from the sidelines, I always told myself that whether a Have or a Have-Not, there are very valuable lessons to be learned from these dramas, and whether my daughter was receiving or giving grief (it certainly seemed she was receiving a lot more than giving, but nobody ever accused a dad of being impartial), my wife and I always did our best to ground her in reality and look for the long-term life lessons that could be taken. I do think, subjectivity aside, that I can safely say my daughter began to show real talent for dance during this time. I can also say, objectively this time, that she emerged from this phase with an inner-strength and confidence that is astounding. As I watch her navigate the social quagmire of the tenth grade, I am exceedingly proud and awed at how well she manages to stay true to herself and her friends, while gliding above the drama that can consume most kids of that age. She never judges others, and always stays honest in helping her friends deal with whatever the current issue is. In and out of the dance world I have watched her handle victories with honest grace and compassion, and failures with resolute determination. She’s my hero, and I firmly believe we have the “emerging talent” years of the competitive dance program to thank for that.

From Girls to Women
As the girls mature into women, things change at dance in a way that I could never have understood if I were not so immersed in it. This phase is not something I came to understand only as my daughter entered it – the nice thing about being a dance dad is that every recital and dance competition you attend features dancers from all the age groups. So that long before my daughter was in high school I have been observing this stage of a dancer’s development. I also have the added advantage of being a high school teacher, and so for my entire career have had the pleasure of seeing how dancers take the lessons from dance into seemingly unrelated arenas, like a math classroom, which really is my domain. Having a daughter in dance always made me pay attention to how older dancers behaved, kind of as a way of glimpsing my daughter’s future. Here are some observations I’ve made over the years, and observations I have now had the pleasure of seeing manifest in my own daughter.

Dance is a Language
This is not metaphor. Dance actually is a language. It took me some time to fully appreciate that. Because of my daughter’s involvement in dance, our family has been marisa-dancewatching So You Think You Can Dance since season 2. It’s a great show to be sure, but I admit at first I was too absorbed in marveling at the physicality of it to understand what it communicates, despite the fact that the judges on the show really do a great job emphasizing this (I always assumed they were saying it metaphorically). But like a child that learns to speak simply from hearing the spoken word and contextually absorbing meaning from the sound, I began to absorb meaning from the movement. The first thing I realized was that unlike languages that use words, dance doesn’t translate to any other language, and communicates things which can’t be communicated any other way, with the possible exceptions of fine art, or poetry. Really good fine art will enthrall and speak to the viewer through infinite contemplation of something static. Really good poetry succeeds at using words which individually can be quite linear, by combining them in a way to create depth and consequently say something the language the poem is written in was not necessarily designed to say. Really good dance? A different thing entirely. It speaks to our humanity on multiple levels, and the fluidity of it allows the choreographer/dancer to tell us stories no written word could approach.

Words are discrete, and a picture is static. But motion is a continuous medium, and the very continuity of it results in an infinity of expression within a finite frame of time and space. It has been said that dance is poetry in motion, but I honestly have come to see it in the reverse. Poetry is dance stood still. I can’t find words to describe this any better, because words will fail here. If you want to know what I mean, watch dancers. And in the same way that second and third languages improve thought processes and imagination, so does dance – but it does so in a way that is magnified a thousandfold because of its unique method of delivery, and because of the world of thought and emotion it opens up for communication. It also is unique in that you don’t have to be able to speak it to understand it. You only have to watch.

Dancers Make the Best Actors
Because of my passion for theatre, I have had the immense pleasure of being both actor and director in various musicals. And here is what I’ve noticed – not all great actors are dancers, but all dancers are definitely great actors. To me there is no mystery as to why this is. Many actors focus on the words they’re saying or singing, trying to pour all of the character they’re portraying into the delivery of the lines or lyrics. Physicality is often an afterthought, or a simple by-product of the emotion they are feeling about the performance. For dancers it’s entirely different. Because of their fluency in dance, they are simultaneously vocalizing and dancing the performance. By dancing I don’t mean the choreography that often accompanies musical numbers, although naturally a dancer excels there. Rather I mean that they are speaking to us in two languages simultaneously. And even those of us not able to communicate with dance can still understand it. So I have often found myself thinking of a dancer “It’s not a je ne sais quois she has. It’s a je sais qu’elle est une danceuse” (yes, you have to speak some french for that one  😉 ).

Dance is Empowering
Okay. So obviously dance results in physical fitness. You can always spot a dancer by their muscle tone, posture and grace in simple movement. The importance of this can’t be underplayed. But the kind of empowerment I’m talking about here is more than that. I flying-marisaremember once at a dance recital there was a senior acro small group number about to start (see what I did there – Dance Dad knows the terminology). It was clear from the opening positions that one of the dancers was going to execute a crazy trick to start the dance. Before the music started there were hoots and hollers from the wings and from the audience, and one dancer’s voice from the wings rang out with “You GO girl!”. I was momentarily taken aback. I think maybe I had just read an article or watched a show where that phrase was called into question as demeaning to women. And then I looked around. The stage and venue was dense with strong, confident young women, certain of themselves and certain of their power. And the dancer who called it out numbered among them. I couldn’t see anything demeaning at that point about what she had said, but on a deeper level I realized just what dance had done for these kids. It showed them what inner strength, determination and dedication could do. And so naturally I began to think about the dancers I’ve taught in my math classroom and I had this moment of revelation. It is exactly that quality that has always made them stand out to me in that setting. Not that they all excel in math, because not all kids do. But that regardless of their abilities in math, there is always an inner strength and peace that says “I know who I am, I know what I can do, and I know how to commit to improving.” Where many students in high school still need the explicit motivation that our culture seems to thrive on too often, the dancers have internalized their motivation in the best way. I can’t say enough how important that is for success in life.

unsung-marisa

Thanks for reading,

Rich

Arithmophobia (Fear of Math): My Thoughts

I’ve been a high school math teacher for 11 years now, and I’ve also been tutoring students privately for even longer than that. Consequently I’ve seen the whole spectrum of math students. Everything from the freakishly gifted to the astonishingly weak, For the most part I think this is fine. Some people are wired for certain things and some are not. I am not wired to be a sprinter. I could train my butt off for years and still not qualify for a track team. I’ve made peace with that.

What I don’t think is fine however, is the growing number of math-phobic students I am seeing. Students whose deep fear of math is so intense that it is almost impossible to determine where their strengths and weaknesses in the subject are. To understand what I mean think of a person who suffers from stage fright so severely that every time they sing in front of even a small group of people their throat closes up and all they can manage is a pathetic croak. Anyone listening would conclude this person is a terrible singer. Yet it may not be true. The neurosis camouflages the talent and it’s impossible to know what the person’s singing ability really is. What makes it worse is that it is extremely difficult to evaluate the cause of poor performance. After all, some people just can’t sing.

In math these students whose fear interferes with their performance very often conclude that they have no ability in the subject, which further feeds the phobia. A seriously vicious cycle that is difficult to break, even after it’s been recognized. So my question as of late has been, what’s causing the increase in math-phobic students?

I don’t have research to back my conclusions. It’s all purely anecdotal. However these observations have been made from the trenches. I see these students every day, in a classroom setting and one-on-one, for over 11 years. Here are my thoughts.

Poor Evaluation Criteria
More and more I am becoming convinced that this may be one of the single biggest causes of arithmophobia. I am talking about the alarming tendency for students’ grades to not reflect their ability, due to poor evaluation criteria. I’ll give you an example.

A simple linear equation to solve.

A simple linear equation to solve.

here is one student’s work, graded:
A flawed solution to the simple equation.

A flawed solution to the simple equation.

and here is another student’s work, also graded:

The equation answered correctly but not traditionally.

The equation answered correctly but not traditionally.

The first student received a mark of 2/3, which rounds to 67%. What are we to take from this? Imagine the student coming home with a report card that says 67% in math. What would the parents conclude? What would an independent observer (like a university) conclude about a grade of 67% in math? The easiest and most likely answer is that this is a student who grasps roughly 67% of the concepts covered in math. With respect to this question and the topic it tests, it means the student grasps only 67% of the concept of solving linear equations. Now based on their work, do you believe that is a true assessment? What would we have this student believe? It’s disturbing to say the least.

But significantly more disturbing is the grade of 0/3 assigned to the second student. This student answered the question correctly, however the traditional approach is to assign one mark per step in the question, and since the student did not show any of the expected work, he lost all marks. Now he has 0%. What would that say to parents and universities? Most disturbingly, what does it say to the child?

Stop and ask yourself what it means to solve an equation. The above equation, translated to English, states that

“There is a number which is multiplied by 4 and then the product is reduced by 3, for a result of 29.”

The instruction “Solve for x” means

“Tell me what the number is.”

Student 2 has successfully done just that. Period. End of discussion. Not only has he correctly answered the question, but in doing so has demonstrated that he understands the question and has the higher level thinking skills to answer it without employing any traditional algorithms. And we work in an educational system which has evolved to tell this student that he is so bad at math he gets a zero. Shame on us. Shame on us all.

So what happens to this student? Well from my experience he either dismisses the subject as “a stupid bunch of rules” (and who can blame him? When the answer is so obvious what value is there in writing down a bunch of steps that do nothing more than add tedium?), or he “learns” that to be good at math you have to suppress your instincts and replace them with the all-important STEPS. And let me tell you something. By the time you get to senior math in high school, there are a lot of steps! There’s no way most of us – myself very much included – could memorize all those steps, know precisely when to apply them, and do so with complete accuracy and precision every time.

Enter fear.

Imagine for a second you are a dog. A puppy. You mean no harm to anyone and in fact are a bouncing bundle of happiness and joy. Unfortunately you have an owner who has anger issues. You’ve discovered that your owner hates it when there is pee on the carpet in the house. The reason you know this is because every time he discovers any he loses his temper and yells. So in order to help, you begin peeing in hiding places around the house. To a dog this makes a lot of sense and is very considerate. Unfortunately all this does is make your owner even more angry, to the point where he smacks you every time he discovers the hidden pee. Result? You are now afraid of the owner, and afraid of peeing. Nothing productive comes of this because despite your best efforts, and despite the fact that you are doing what you think is right, you are still getting in trouble. That is a recipe for fear. And that is what happens to students who do what they think/know is right, but get rewarded with marks like 0/3 for their efforts. How can a person continue with a positive attitude under those kinds of circumstances?

What also happens to a large number of students is that over the years, as they fail more and more to memorize the right “rules”, they become more and more disillusioned with themselves. The mathematics becomes totally obscured by the algorithms, to the point where students believe that the algorithms are the mathematics, and can hardly be convinced otherwise.

I tutor a student named Randy and she is in grade 7. Here is a question from a test she wrote recently.

Sam has answered the question “7 – 3 ½” with “4 ½”. Sam says this is because seven minus three is four, and then there’s an extra half to make four and a half. Is Sam correct? Explain.

Here is what Randy wrote:

Sam is not correct. To answer the question you have to convert 7 and 3 ½ to improper fractions, then subtract the numerators, then convert your answer back to a mixed number. This is what Sam should have done:
7 – 3 ½ = 14/2 – 7/2
= 7/2
= 3 ½
So the correct answer is 3 ½

For this answer Randy received a “2+” which is a mark out of 4, with these comments from the teacher: “What was wrong with Sam’s thinking? How could he modify his strategy so that it would work? Expand on your answer.”

Hmmmmmmm. My thoughts as a teacher were immediately “Those comments would have made good questions for students to answer on the test instead of criticisms of Randy’s answer”. In any case let’s have a look at how this result impacted Randy.

So marks out of 4 like this one can be roughly converted to percentages, which they ultimately will be for reporting purposes. A mark of “2+” converts to around 65%-70%. I implore you, dear reader, to tell me just exactly how Randy has shown her capabilities in subtracting mixed numbers from whole numbers to be 30% less than perfect. The message to Randy?

Because you were unable to extrapolate from the word “explain” that I, your teacher, was expecting you to delve into the mind of a person who, unlike yourself, can not subtract mixed numbers from whole numbers, I conclude that you, Randy are a mediocre math student, at best. Despite the fact that the question was in two parts (“Is Sam correct?” and “Explain”), and that you addressed both correctly, you should have known that what I was really looking for was for you to help Sam understand why his thinking was wrong, despite the fact that it did not say this anywhere in the question and despite the fact that Sam is a fictitious person. Please work harder from now on so that you may become a better math student.

Randy was in tears over her results. She said she was sure she understood the material going into the test but she’s just bad at math and she hates it and she is never going to be good at it. It took quite an effort on my part to show Randy that she completely and perfectly understands subtraction of mixed numbers from whole numbers and that the real flaw is the question. I’m not sure she is totally convinced and her grade in math will certainly not reflect what I know to be true so it will be a difficult pill for her to swallow. Randy is developing a serious case of arithmophobia based on experiences like this. She is not wired to “know what the teacher means”. She reads instructions and takes them literally, and then answers them as best she can, usually correctly. But since there is more wrapped up in the evaluation criteria than is revealed in the question itself, Randy is rewarded for her efforts with marks like “2+”. To her this makes math incomprehensible, and who can blame her? To her math is now a mysterious subject with weird expectations that you have to “just know”, and what hope does she have of being able to do that?

So what can we do? The answer is as simple to state as it is difficult to implement in today’s education environment:

Let’s start teaching MATH again. And when we grade a student’s work let’s stop comparing what they did to some sort of “template of perfection” and instead evaluate what the work we see says about the student’s fundamental understanding of the mathematical concepts. Solving an equation means finding the values of the variable that make the equation true. The fact that we have algorithms for solving equations is wonderful and essential for very difficult equations, but let’s not punish students who are able to understand and solve without the algorithm! Let’s celebrate those students because they are the ones who really get it. The algorithms can be introduced and reinforced later when the equations get harder, but it serves no purpose to tell a student like that they are bad at math, for they are truly not. And for students like Randy? Let’s throw away the rubrics and fancy words and assess what their work tells us about their abilities. If we want Randy to extend her knowledge to be able to help Sam modify his strategy so that it will work let’s help her with that, but there is very little value in tying her grade in math to that ability, unless that ability is very specifically what we are trying to teach and assess, in which case we need to ask ultimately how much is that worth and how should it be reflected in the grade that she will use to determine her performance?

Arithmophobia is real and it is getting worse each year. We must change what we are doing if we want to reverse the trend.

Thanks for reading,

Rich

The Death of the Mistake

(Disclaimer: NOT ALL PARENTS are guilty of what I describe in this blog, so please don’t take it personally. But many are. Far too many.)

I’ve made a lot of mistakes in my life. I imagine you have too. Some of mine are pretty indelible for me.

Like the time my friend and I were playing with fire (literally) and almost burned down a hotel. We were scared to death and actually grateful we got caught.

Like the time I decided I could get through that intersection before the car coming from the left got there. Result? One totaled car that wasn’t even mine. It was my girlfriend’s car.

Like the time I thought I could get away without studying for my final exam in STAT 331 and still scrape a credit in the course. I earned a 42. I asked the prof to remark the exam which he did. The mark went down.

I didn’t like any of these or the countless others when they happened. Actually they felt pretty miserable. Yet each one has had an impact on decisions I made later in life and each one of those failures thus resulted in bigger successes. This is not a revolutionary concept. The phrase “we learn from our mistakes” is not new. But have you ever considered exactly how true it is? We aren’t born with an abundance of knowledge. In fact we are born with almost none. We know how to do things like breathe and cry and fill diapers, but we can’t even control those actions much. At first, all the knowledge we accrue comes from our innate curiosity and willingness to take risks. What’s funny is that as babies we don’t even know we are risking anything. We’re just really curious. Watch all the stuff a baby is willing to put in his mouth. You’ll know exactly what I mean. So babies try things and sometimes the result is pleasant or satisfying and other times its not. Each experience whether success or failure goes into the data bank and both guides subsequent experiments and imbues us with confidence regarding our ability to reproduce successes. In this way it is completely correct to categorize both “success” and “failure” as positive outcomes. And yet we have attached so much negativity to the word failure that it has become a thing to be reviled and feared … avoided at all costs. Which is a true tragedy, because success in the absence of failure is yin without yang.

As time passes the culture we grow up in imposes a formalized education, mainly because there is value placed on certain nuggets of knowledge. This happens in the form of school. And that’s where I come in.

Sort of. I teach high school so I guess I come in about 10 years later. After 10 years of a system which has sadly killed the mistake. Kids are no longer encouraged or allowed to experiment. They have to “get it right” the first time. Many parents spend insane amounts of energy making sure their children never experience failure, defeat or mistakes. A friend of mine calls this phenomenon “the snowplow parenting” model. The parents walk ahead of the child, plowing all obstacles out of the way, frantically making sure that no failure is ever experienced. As the child grows and the potential obstacles increase, parents run themselves ragged continuing to pave a smooth way. The effect this has on the kids is incredibly frightening. The child grows up not ever really experiencing a failure, but watching parents become more and more neurotic making sure this “failure monster” never has a chance to get near their kid. It’s a doubly-bad edged sword. First, no failure is ever experienced so there is no chance for the best kind of learning and second, the children pick up on this deep fear of failure and when they find themselves faced with the potential for a mistake they freeze in terror at the possibility. In short, they are simply not equipped to deal with anything but a smooth road, and lack the understanding and confidence that comes from having failed.

So what I see in my math class is kids who are petrified of assessment. I have seen kids cry when they earn a mark in the 90’s on a test. Worse, I’ve seen kids with marks in the 90’s crying when they come in to write a test because of how afraid they are that they might make a mistake. And I’ve had to defend marks to parents who insist to me not that their child earned a higher mark, but that their child needs the higher mark. In grade 9. A grade that no university or college even remotely cares about. A grade for which no scholarships are awarded. Yet the child needs the higher mark. Lest they experience failure.

This phenomenon may actually be the single biggest threat to our culture. Thanks to Snowplow Parents we are raising a generation of kids who have never had a chance to experiment and fail. Never a chance to pursue curiosity, which is the spark for innovation. So what we get is anxiety-ridden underperformers with huge self-esteem issues, fostered by parents who have made it clear that the child is not capable of fending for themselves and thus needs the parents’ involvement every step of the way.

Parents, please. Take a step back. Watch them do it themselves. Watch them fail and celebrate the failure. Mistakes are critical for evolution. Let’s bring them back. Let’s start the Mistake Revival.

Thanks for reading,

Rich

A Short Lesson on Credit Cards

Many people who use credit cards understand how they work, but many don’t. I was teaching a class on this the other day and a student of mine pointed out that she thinks her parents don’t know about what I was teaching, and suggested I write an article. So I thought, why not? The math can get a little confusing, so I’ll avoid most of it and just give the answers. Keep in mind this is a lesson I do with high school students, so I ask your forgiveness in advance if you read the whole article and never encounter anything you didn’t already know.

First things first. If you pay your credit card balance in full before the due date each month, you win. You are not paying any interest at all. So for example if you bought something at the beginning of your credit card cycle for $1000, the bank actually lent you the money to buy it without charging any interest, meaning you have owned something for a month before you had to pay for it, and it was at the complete and total expense of the bank. Not bad. In fact, if you really want to be clever, you can buy a $5000 television, charge it to your credit card, go from the store to the bank and deposit $5000 into a one-month GIC, and when the credit card statement comes withdraw the $5000 from the GIC to pay the bill. The GIC will have earned interest for a month so in effect that bank will have paid you to watch their television for a month. Nobody does this really, but in theory there’s no reason why you could not. Pretty cool.

So for people paying their balance in full each month, more power to you! Especially if you have some sort of points earning system on your card, which I’ll get to shortly.

Now for those who do not pay the balance in full, a short lesson on what happens. First, I’ll explain what the banks do about the interest.

As I said before, when people pay the balance in full, interest is never charged. But that doesn’t mean it’s not calculated — it really means it’s forgiven. So a purchase made 20 days before the statement date does accrue 20 days of interest (accrue means interest is added on), but it’s forgiven if the balance is paid in full. On the other hand, if the balance is not paid, that 20 days of interest kicks in.

I’ll use an example showing a just a few purchases. Here goes.

Assumptions:

  • No balance at beginning of cycle
  • Credit card interest rate is 20% (most are slightly below this as I type, but not significantly so — contrast that with current prime lending rate in Canada which is 1%!)
  • Cycle runs from January 1st to February 1st
  • Minimum payment due to credit card company is 3% of the outstanding balance (this is normal).

Purchases:

  • January 1: $2500 on a 54-inch LCD 3D TV. Great deal post holiday.
  • January 5: $400 on 3D DVD’s. Turns out watching regular TV on a 3D TV is a tad boring.
  • January 7: $200 in snacks from Costco for the Avatar party you’re hosting at your place.
  • January 10: $50 for a new pair of 3D glasses — turns out you can’t drop them in a punch bowl and expect them to still work.
  • January 18: $300 for a new XBox 360 gaming system because you ran out of 3D movies to watch.
  • January 25: $200 for new games because it turns out the one your XBox came with kind of sucks.
  • January 31: $150 for cool Halo controller, with helmet.

For the record, you spent $3800 using your credit card. Now suppose the minimum payment is $114, which is 3% of your outstanding balance (this is normal), and that’s all you pay. The credit card company requires that you make this minimum payment to avoid penalties, but they don’t really explain about how you’ll be penalized anyway with interest.

Here’s what happens. Your balance the moment the $114 is received by the bank will not be reduced to $3800 — $114 = $3686 as you might expect. In fact what will happen is your balance will immediately have $66.49 in interest added to it.

So your actual new balance will be $3752.49.

But it gets worse. You see what happens is that all your purchases starting with the very first one were interest-forgiven until the moment you didn’t pay the full amount. At that point what the bank does is they subtract your payment from the earliest purchases (in this case from the $2500 TV purchase), then they convert the 20% interest to a daily rate, which works out to about 0.07% per day, and calculate interest on each purchase using the number of days since the purchase was made. And the clock keeps ticking, so that by the end of the next statement period, which would be March 1, another 28 days of interest accrues on the balances. That would be another $71.03 bringing your balance up to $3823.51, not including any purchases you make in February. And in case you didn’t notice, your $114 payment has been completely eaten up by interest after only 28 days, plus you now owe $23.51 more than you spent. That’s after only 1 month and having made a payment of $114!

It gets even worse, if you can believe it. The purchases you make in February will be interest forgiven until March 1, however because you have old purchases from January on your account now, any payments you make on March 1 are applied to those purchases first, starting with the oldest, and that means that your February purchases are that much harder to repay in full, which in turn means that they will start accruing interest the same way your January purchases did the moment they are not paid in full.

When you consider that on March 1 you have to pay for all your January purchases, plus an extra $23.51 before you even have a chance at paying for your February purchases, you can see how difficult this gets, and how quickly it can spiral out of control.

OK. So lesson number one is always pay your balance in full. It’s the most important lesson about credit cards. So important that if you can’t do it, you should not be using your credit card at all. You will quickly max out your credit limit and then lose the ability to use it for purchases, and simultaneously be saddled with huge interest charges that you’ll have to manage.

At this point many people say that credit cards are evil and they should not be used. “If you don’t have the money to pay for something don’t buy it” they say. “Always use cash” is the motto for these people. They make a lot of sense, but they are wrong. Further, not only are they wrong, they are for the most part overpaying for their purchases!

You’ll have to allow me to explain that part. It seems to make no sense at all.

So here’s the deal. When a merchant decides they want to accept credit cards as a form of payment, they need to get a merchant account. They’ll generally rent a terminal from the bank to process the transactions. They also pay a merchant fee to the bank for every transaction, generally 2%-4% of the sale price, which means that they earn less on purchases paid for by credit card than they do on purchases paid for in cash. At the end of a day of business the bank will deposit the total for the credit card transactions less the merchant fees into the account of the merchant. So it costs the merchant money to accept your credit card, which is money they will do their best to build in to the price of the goods and services they provide, to the extent that they can without overpricing.

For most merchants this is a cost of doing business and though they may not like it they accept it for what it is because many customers will shop elsewhere if they can’t pay by credit card. It’s also part of the reason why some stores offer a discount if you pay in cash. Sure cash is harder to trace, but beyond that a merchant can afford to sell a product for cash at a lower price and still make the same profit or even slightly more if the offered discount is less than the merchant fee. So there’s a slight over-payment when you pay full price in cash for something that you could have used a credit card for, but it’s not really fair to categorize it that way since if you pay with a credit card that over-payment disappears and in either case you have received a good or service for the same price. So that’s actually not what I mean when I say people who pay in cash are overpaying.

The over-payment I’m referring to actually has nothing to do with the merchant. It’s really the points on the credit card that you miss out on when you pay in cash. Most credit cards today have some sort of points system attached to them whereby you accumulate points through purchases and then redeem them for merchandise or travel. For example earlier this year I paid for a return flight to Kelowna, BC and 4 nights in a hotel all with points.

Stop and think about that. The airline didn’t give the trip away. They can’t afford to. The hotel didn’t rent the room for free for the same reason. Both the airline and the hotel were paid by Visa. But where did Visa get the money? Not from me — I pay my statement in full so I never pay interest, which means Visa pays for my stuff then I give them the money back at the end of the month so they break even. Aside from my annual fee of $60, Visa is not making profit directly from me. The answer to where they get the money is the interest of other credit card holders mostly, merchant fees and annual cardholder fees. That’s $60 annually from me.

So what? Well let’s say in a year I spend $100,000 on Visa on some list of goods and services, and someone else spends $100,000 in cash on the same list. At the end of the year my wife and I go to Vegas and stay at The Venetian, all on points, a trip which would cost around $3000 in airfare and hotel. Mr. Cash does the same, but pays cash. They have now spent about $103,000 or so, but I’m at $100,060 (remember to add my annual fee) and we’ve gotten the exact same stuff. If you think a little more about it, if I spent $100,000 on Visa then the merchants where I shopped paid 3%, or $3000 of that in merchant fees. There’s the money for the trip. But the important part is Mr. Cash spent $103,000, and I spent $100,060

See? The cash payer overpaid.

Of course, if you don’t pay your balance in full each month all bets are off. In that case you would be paying for my trip to Vegas. And nice as that is, I don’t expect you to do it.

The moral is, put everything you possibly can on a credit card with a points system. Pay all your bills with it. Buy a car with it! But always always always pay your balance in full (if you can’t pay your balance don’t buy the stuff). You’ll be surprised at the “free” things you get and none of those things would come to you if you pay in cash.

Thanks for reading,

Rich

Sometimes, the Door Is Down the Hall

Today my blog is about one of the most important things I’ve learned as a teacher, and specifically as a teacher of math. I’m going to start with a story about a kid I tutored for a while, many years ago.

When I was younger and just starting to realize I had a passion for math and for teaching, I firmly believed that anyone could understand math and be good at it. Some people took to it more readily than others, but I was certain that given enough time and effort, every single person could excel.

Then I met Lief (not his real name).

Lief came to me when he was in grade 6, and our first tutoring session was about math questions involving time. The question we worked on was something like “Harry leaves home at 12:05 pm and arrives at his destination at 1:30 pm the same day. How long did the trip take?”. Lief was really struggling with the question, but I knew that I could explain it in such a way that he would not only be able to determine the correct answer he would fully understand how we did it and be able to answer many more similar questions. As my students would say, I have mad skillz when it comes to explaining math.

Boy was I wrong. I spent an hour with Lief and I used all my powers of teaching and explaining to no avail. Strewn about us were diagrams, pictures of clocks, number lines, a watch and even part of a model Volkswagen Beetle (don’t ask me why, I don’t remember). Lief just could not understand what the question was asking and why the answer was 1 hour 25 minutes (see how I threw that in there so you’d know if you got it right? 😉 ). I learned a valuable lesson that day.

Some people just aren’t wired for math. And that’s totally OK of course. Contrary to popular opinion, math is not a critical life skill. Aside from people like me I can’t think of a single person that needs to be able to complete the square of a quadratic function given in standard form in order to determine the coordinates of the vertex of the parabola. Proof? You most likely have no idea what in the world I was talking about there and I bet you do just fine. I know at least that you own some sort of electronic device capable of connecting you to the internet. That says something.

So why is this blog titled “Sometimes, the Door Is Down the Hall”? What am I talking about, you ask? Well you wouldn’t be the first to ask that. Allow me to explain.

Where I live in Ontario, Canada, students attend high school for four years — grades 9 through 12. During that time, in order to be awarded their high school diploma, they must successfully earn three credits in math. For most students, that means a grade 9, grade 10 and grade 11 credit, though some do grade 9, grade 10 and grade 12. It means that math is optional in grade 12, if all you want is a high school diploma. If you want a post-secondary education however, like college or university, you will most often need to take math in all four years of high school, and also be sure to choose the right math courses for your intended post-secondary program.

At each grade, there are choices of which math course to take. There are different paths and they don’t all lead to the same place. For example, a student who intends to study math or science at university will take what’s called “Academic” math in grades 9 and 10, then “University prep” math in grades 11 and 12. Conversely a student who intends to go to college to learn a trade will likely take “Applied” math in grades 9 and 10, then “College prep” math in grade 11 and maybe also in grade 12, depending on the requirements of the college program. Some students take what’s called “Essentials” math in grades 9 and 10, then “Workplace” math in either grade 11 or grade 12. These students are either not planning to attend a post-secondary institution or else are planning to go into a field that has nothing at all to do with math.

Phew! So that was kind of boring to read, right? But if you read it you may have noticed the glaring flaw in the system. A student must decide on a career path in grade 9. When they are 14 years old. Actually they have to pick their grade 9 courses when they are still in grade 8, so they and their parents have to make the call when the student is 13 years old. Who the heck knows what they want to do with their lives at the age of 13? When I was 13 I wanted to look at girls, play video games, eat steak as an afternoon snack and look at girls. And then look at girls. I had absolutely no idea what I wanted to do with my life. As a matter of fact now, at 43, I still don’t know what I want to do with my life (except for the looking at women part — I still do that and am lucky to have a wife that is exceptionally fun to look at). But I do know that I am happy with what I’m doing right now. Maybe that will change, maybe it won’t. But the key to my happiness is that I am doing something I am good at and that in turn makes me good at it. Read that last sentence a few times. It seems confusing but it isn’t. Try doing something you suck at for a long time. Keep telling yourself that you’ll get better if that makes it seem worthwhile. But I think you’ll find out that when you’re not good at something you are miserable doing it and then you are not good at it.

So how does this manifest in high school? Well it may seem obvious that since very few 13 year old kids have any clear idea about what they want to do when they finish high school — let alone as a career — that they choose the option that keeps all the doors open. In Ontario, that means that they will usually choose grade 9 academic math, because if they don’t they are closing the door to a post-secondary program that requires math. They do it again in grade 10, 11 and even in grade 12. I can not begin to count the number of students I have taught who have struggled mightily in math who then sign up for the hardest math course the following year because they don’t want to close doors. I’ll illustrate with an example. Good ol’ Hanz.

You might remember Hanz from “Steer With the Skid”. Hanz is a hard-working kid who does not have a lot of natural ability in math. By not a lot I mean he’s terrible at it. And please, before you object and say nobody who works hard can be terrible at something, look around. Some people are wired to be awesome at certain things and terrible at others. Some kids are born athletes, some are born artists, some are born mathematicians and some are born poets. You can improve your abilities in almost anything but that doesn’t mean you can excel in almost anything. Personally, as hard as I might have trained, I would never have been an Olympic sprinter. My legs are too short and I don’t have the reflexes. I’ve made peace with it.

So back to Hanz. Hanz doesn’t want to close doors, so he takes Calculus in grade 12. Currently in Ontario the course is actually called Calculus and Vectors. It’s the two hardest math topics in high school grouped together in one spectacular ride. Hanz has been miserable in math class ever since grade 9. He works hard, and puts in the time, but the most he can muster are grades in the 60’s, and it eats him up. His hard work is constantly rewarded with what he considers to be mediocre grades. He’s miserable because he’s convinced that he can’t be successful in life unless he’s successful in math and his definition of successful in math is marks in the 90’s, something he’s never been able to do. In trying so hard to keep a door open, Hanz has missed the fact that for him, there is no door marked “math”. He can’t see that if a program requires Calculus and he takes it and earns a 51% he won’t get in anyway. It’s a fruitless exercise. Yet every time I talk about this with Hanz or his dad Franz, they both insist that Hanz has to stay in Calculus so that he can keep his doors open. That’s when I shake my head and say “Sometimes, there is no door. Walk down the hall.”

See, if Hanz could recognize that there is no “math” door for him, he would be compelled to walk down the hall and see what other doors there are. If Hanz would spend more time in situations where he has natural strength, he’d know what those doors are and what lies beyond them, and he’d be so much happier. Unfortunately it’s extremely difficult to convince Hanz of this, and he spends all his energy working at something he was not wired for, spiraling further and further into self-loathing and often depression. I’ve seen it many times. I’m not exaggerating.

Now please, before you go off wondering how I can call myself a math teacher and be so willing to write kids off, understand that’s not what I am saying. I teach all levels of math. I am just as happy teaching someone like Hanz how to plan a family budget and the evils of credit card interest as I am teaching him how to take the derivative of a sinusoidal function that has been composed with the square of a logarithmic function in order to determine the instantaneous rate of change on the curve at the place where it intersects with a given exponential function. I work just as hard either way, and my reward is always Hanz’s success. It just pains me to see kids like Hanz convinced that they will end up “homeless under a bridge” (this is a saying my students have when they decide they are going nowhere in life) if they can’t do the derivative question. Honestly though, how many people can? And why on earth would most people need to? The derivative question is an exercise in abstract thought that is beautiful in its way, and critical for people going into a field where they have to solve high level math or science problems all the time, but it’s not the definition of intelligence or success.

Students like Hanz often ask me what courses they should choose when they are picking for the following year. I always say the same thing.

Me: “What are you good at?”

Student: “Well I’m good at <insert non-math or science discipline here> but that doesn’t get you anywhere so I need to take <insert completely inappropriate math or science course here>.”

Me: “Why would you take something that makes you so miserable?”

Student: “Because I need it to be successful. I need to keep my doors open.”

At that point I generally ask them how they intend to become successful in a field that requires them to be good at something that makes them miserable. They really never have an answer for that. Except for the door thing. My advice then is for them to take courses they enjoy, and that they excel in. Happy people who excel at what they do are always successful. Find one and ask them. You’ll see what I mean.

Thanks for reading,

Rich

Steer With the Skid

When you learn to drive in Canada, one of the most important lessons is what to do when your car enters into a skid. It’s not a question of “if” really. In Canada, it’s definitely “when”. Usually it will happen in your first winter of driving, so you’d better be prepared. The technique is to steer with the skid. It means that you have to fight your natural urge to steer in the direction you’d like for your car to go, and instead actually aim your wheels right at that concrete median your car has suddenly decided to crash into. Then, once you and your car agree on the direction you want to go, you gently steer the car away from disaster. It works, and in fact it’s the only way to handle the situation, except perhaps throwing open your car door and launching yourself out onto the pavement.

The physics behind why it works are fairly straightforward. When you enter into a skid your car has momentum which is carrying it in a direction that is usually not conducive to healthy living, and there’s nothing you can do about it because the friction between your wheels and the road has suddenly been reduced significantly by ice, water, gravel or some other non frictiony substance. This means that gross corrections where your wheels are pointed at an extreme angle to the skid won’t work, because the momentum of the car is overcoming the minimal friction at the wheels. So by pointing the wheels in the direction of the skid you force the momentum to cooperate with your goal of non-disaster, and then make relative small corrections which work because the little bit of friction you do still have is only slightly off from the massive momentum. Baby steps of correction eventually get you out of trouble. And it happens pretty quickly, as anyone who has ever done it can attest to. When you don’t understand the physics, it almost seems like magic.

The reason it has to be taught though, is because it’s so counter-intuitive. Aiming in the wrong direction so that you can go the right way feels like slowing down so that you can speed up. As it turns out, this driving lesson is actually an incredibly important life lesson as well. It shows up in so many ways. I’ll illustrate with a few examples of skids.

Skid 1: The Determined Daughter

Imagine this scenario. It’s 5 minutes before you have to leave the house to walk your daughter to school, and she is insisting that she does not want to wear a jacket. The problem though, is that you happen to know it’s 3° Celsius outside. If your daughter is anything like mine and she has her heart set on not wearing a jacket then you have 5 minutes to fight and win World War III. Good luck. This, ladies and gentlemen, is a bona fide skid. Your car is careening into two kinds of barriers. Frostbitten Child and Late Slip. Solution? Steer with the skid. Instead of fighting the momentum, agree that she does not need a jacket, but bring it with you and leave. If you really want to be fancy, don’t wear yours either. You carry hers and she can carry yours. Or you carry them both — it’s not really important. Once again if your daughter is anything like mine she will have a true aversion to discomfort, which is something she’ll start to feel within about 20 steps. She’ll ask for the jacket. If you didn’t wear yours, you can ask her for yours before she asks for hers. That will make it okay for her to ask for her own and still save face. Skid averted. No frostbite and no late slip.

Skid 2: The Quadratic Quandary

Here’s another scenario that I often encounter at school. Let’s say I’m helping a student solve a quadratic equation (apologies for this if you don’t know what that is — feel free to skip this part). Take this one for example:

x² − 5x − 14 = 0

If you’re a math teacher you know that a goodly portion of students unused to solving quadratics are going to try and isolate the variable the nice old fashioned way. You also know that it won’t work – totally destined to fail. You might be tempted to intervene before they try, and suggest a different method, but if you do then in the back of their mind they’ll always be wondering why not just isolate.

The best strategy pedagogically is to let the student try it. Agree that isolating the variable is a good plan. Help them with the operations – steer with the skid. As you work with them to isolate the variable generally this will happen:

x² − 5x = 14

At which point you can have a very valuable discussion about why we are stuck. The student may try some fancy footwork here, but thanks to you being on their side, you can navigate it with them and they’ll see that there’s nowhere to go. Then you can gently steer them toward other options. What do we know we can do with quadratic expressions? Factor them. So what? Let’s find out. I won’t get into the actual solution here, because it’s not important right now and in any case if you were following until now I’m fairly confident you can finish up. But for those who need to know, the solution is x = 7 or x = −2.

Skid 3: The Perturbed Parent

Once more this scenario is one I encounter as a teacher, but in fact it generalizes to any customer service industry. I actually really learned this well in my previous life as a software engineer when I would spend quite a bit of time on the phone with our users who would call when they were struggling with our software. Readers who are teachers will understand this situation pretty well. It goes like this:

Hanz is a student in your class who has written a math test for you and earned a fairly low grade – say, 54%. Hanz has plans to go to university (or college if you’re American – here in Canada college doesn’t mean quite what it does in the States) to become a doctor. Hanz needs a high school average of 91% to get into medical school. Thus the 54% on your test is a somewhat sub-optimal result. The next day you get a call from Hanz’s father, Franz. Franz opens the conversation by informing you that he is a lawyer, and that he has a real issue with the mark you gave Hanz on the test. Franz tells you that Hanz is extremely gifted in math and has always earned grades in the 90’s until your class. Hanz worked extremely hard preparing for the test and his tutor guaranteed that he was ready to ace it. Franz concludes that the whole mess is therefore your fault, because you are an unfair marker, a bad teacher, a horrible human being and quite possibly a chronic hater of children. Franz insists that you raise Hanz’s mark so that it is consistent with Hanz’s abilities and also consistent with his goal to become a neurosurgeon.

At this point it is incredibly tempting to get defensive, or be offensive. After all, Attorney Franz has attacked your professionalism (unfair marker, bad teacher) and your motivation for being a teacher (child-hater). Furthermore, if you know Hanz you know that “gifted” and “math” are not two words that you would put together in a sentence describing him, unless you could liberally sprinkle said sentence with the words “extremely” and “not”. However there is nothing to be gained by this response. All it will do is exacerbate the situation.

Instead, steer with the skid.

First, tell Franz that you understand why he’s upset. In fact you are upset by the grade as well – who wouldn’t be? Ask him about the hard work Hanz put in to prepare. Commiserate with Franz about the difficulties of watching young people work so hard and then not have it pay off. I am not being facetious here, and neither should you be in a situation like this. Put yourself in Franz’s shoes. Hanz worked hard, and hard work is supposed to equate with success. So why didn’t it? You and Franz can discuss this question. You can provide Franz with some questions to ask the tutor about the work he does with Hanz. You can recommend that Hanz come and see you to go over the test to see where the disconnect was. After all, since Hanz is so talented in math, there must have been a disconnect. When Franz sees that you have no intention of fighting him, his momentum joins yours and you can then steer him in the direction he needs to go, which is ultimately to realize that you did not “give” Hanz his mark – Hanz earned it. And getting to the bottom of why he earned a mark as low as he did is what you both want so that you can both help Hanz. This will ultimately help Franz see that it is Hanz who was at fault, and will also eliminate the need to address some of the more insulting parts of Franz’s opening tirade. It is entirely possible that during the conversation Franz will admit that the “marks in the 90’s” comment was not completely true, and referred to 2 quizzes Hanz wrote when he was in the 3rd grade. By the end of the conversation, Franz will know that you are on his and Hanz’s side, and that the energy of all three people is channeled in the same direction – not the direction of the skid anymore!

There are countless other scenarios I can come up with, all of which I have experienced personally (no, I never taught anyone named Hanz …), but the theme is always the same. A situation arises and the temptation is to fight against it, but fighting only escalates the problem. The solution is counter-instinctive and often requires strong self-control but pays huge dividends. Leverage the momentum of the skid for a quick and successful course correction.

Works in cars, works in life. Steer with the skid.

Thanks for reading,

Rich

Switch the Side, Switch the Sign?!!?

You can always judge my level of incredulity by my combination of punctuation. Two exclamation marks bookended by two question marks is a high level indeed. It’s the DEFCON 1 of incredulity. It comes from the way I’ve seen a lot of my students conditioned in algebra. It’s extremely sad. I’ll explain, but I have to start with a story about something that happened last week.

Thursday night I came home from play rehearsal and got the debrief about the household goings-on from my wife. Turns out my daughter, my 11-year old angel of happiness, was crying for something like 2 hours while I was gone. Dads out there with daughters (and I guess daughters with dads?) will know that there’s a special thing going on between dads and their girls. I think the best quote I ever read to describe it was this one:

Certain is it that there is no kind of affection so purely angelic as of a father to a daughter. In love to our wives there is desire; to our sons, ambition; but to our daughters there is something which there are no words to express.
– Joseph Addison

So when I find out that my daughter was so miserable, a part of me curls up in the fetal position and cries too. But you want to know what made it worse? What made it even more upsetting? The source of her pain was … algebra. Algebra! Her first algebra. A person’s first exposure to algebra should be special. It should be life-defining. It should be a cherished memory that warms you on command. A polished jewel of contentment forever residing at the center of your soul. And yet here’s my daughter, crying for 2 hours, and it was because of algebra. And I wasn’t home.

Talk about two ways to break my heart. Unacceptable!

So I dug a little deeper. My wife told me that my daughter was doing question after question, getting them right, and crying that she didn’t get it. My wife, no slouch in the math department for sure, was explaining the process, but for some reason it wasn’t getting through. My daughter just kept insisting she didn’t get it, all the while getting questions correct. How does this make sense? In what universe can a child keep getting questions right and through tears insist she doesn’t understand? The answer is because she was just following orders. The old “Switch the side, switch the sign” gambit. Consider this question she was working on:

x + 3 = 7

x = 7 – 3

x = 4

Correct, right? And easy too? So why was she so miserable?

It’s because she had no idea why she was doing what she was doing, or what any of it meant, and certainly no way to tell if her answer was right. She was right by accident, and because she was following a bunch of rules. In short, she wasn’t doing any math at all. She was, for all intents and purposes (or for all “intensive purposes” if you’re one of those people who hears sayings but never sees them written down) a trained monkey repeating a task. And nobody wants that … except for maybe the monkey because they get a lot of rewards for stuff like that … but no human wants that. And my daughter is exceedingly human.

You see, here’s what she was taught (or at the very least, to give her teacher the benefit of the doubt, it’s what she thought she was taught): To get the variable alone you have to move the number to the other side. If it’s plus you do minus and if it’s times you do divide. If it’s minus you do plus and if it’s divide you do times. Ouch. So much wrong with this I don’t even know how to start. But I do know that it’s taught this way so often that I have students who think that’s what algebra is. And I know of one teacher who used to have her students repeat the mantra “Switch the side, switch the sign.” I used to ask those students what they do if it’s multiplication or division. They said that’s when you don’t switch the sign. Ooooookay then.

So here’s the thing. When students are taught “rules” for solving equations they are not learning math. They are learning algorithms. An algorithm is a sequence of steps you follow to complete a specific task. You don’t need to know why, and in fact the reason algorithms are so powerful and so common is because you don’t need to know why. Long division is an excellent example. Many of us remember how to use long division to get the answer to 97654 divided by 7. But how many of us know why it works? The algorithm was designed to turn humans into calculators so that mathematicians didn’t have to do the tedious work. In WW1 there were literally rooms full of people – called calculators – who would do repetitive tedious calculations assigned to them by codebreakers. The codebreakers knew why the calculations were required, but the volume of work to do it was so vast that if the breakers themselves were to do the work they’d never decode a single message. So calculators were invented. They were people. A lot of them. And they were good at algorithms. But they didn’t know any math. Of course nowadays we have little computers that do the same job, but the concept is the same. A computer doesn’t think – it only follows instructions. It is excellent at executing algorithms. BUT THAT ISN’T MATH!!!

Ok. Back to the algebra, and my daughter. Saturday morning we were sitting in the family room, still in our pajamas, and Phineas and Ferb had just ended. The time was right. I told her I was going to help her with algebra but first she needed to forget everything she’d learned thus far. She happily agreed and put the misery in some invisible incinerator. Ahhh. Square one. Then we had this conversation:

Me: “Imagine I split your class up into groups of 2. Pick a partner.”
Her: “Alyssa!” (this was meant to be obvious to me)
Me: “Ok, now every pair has to pick one person for the blue team and one for the red.” (blue is her favourite colour – I’m not a rookie)
Her: “Blue!”
Me: “Ok, we’re going to play a game. Blue team goes first. Here’s the game. Pick a number but not a hard one. Don’t tell red team what it is. Now your job is to give Alyssa one hint, and if she gets it right you both get a point. Otherwise nobody scores.” (yeah, lame game, I know – but there are points and a blue team so she’s right on board)
Her: “Ok. My hint is it’s my favourite number.” (I saw this coming a mile away, and had a plan)
Me: “Right, Ok. But here’s the thing. You want to be SURE Alyssa will get it right. What if she can’t remember what your favourite number is? You want to give her a clue that will work for sure. And no using your number in the clue!”
Her: “It’s my birthday.” (Ha! I saw that coming too)
Me: “What if Alyssa forgot your birthday?”
Her: “How could she? She’s coming to my party!”
Me: “Good point. But what if she thinks your birthday is on a different day than the party? After all it is. You want to be sure she’ll guess your number, so make the hint foolproof.”
Her: “Ok, I get it. My hint is my number is 5 less than 10.”
Me: “Awesome! Ok, I’m Alyssa. Is it 5?”
Her: “You knew that already because you know my favourite number.”
Me: “Good point. Ok, here, it’s red team’s turn. If you increase my number by 7 you get 12.”
Her: “Hey you can’t pick the same number as me!” (Success!!!!)
Me: “Yes I can I can pick any number I want. Ok your turn.”
Her: “If you cut my number in half you get 10” (ooooh, nice one)
Me: “20?”
Her: “Yes! Ok, give me one now!”
Me: “If you multiply my number by 2 and then add 1, you get 13.”
Her: “6?”
Me: “6? Why 6?”
Her: “Because 6 x 2 is 12 and 12 + 1 is 13.”
Me: “Nice! Ok, you go.”
Her: “If you add 67354 to my number you get 90543.”
Me: “Ummm, are you going to know if I got it right?”
Her: “No. But you always get it right so I want to know the answer.” (Love her – I always get it right? She needs to talk to my wife!)
Me: “How am I supposed to get it? Those numbers are huge!”
Her: “Just do 90543 minus 67354!”
Me: “Right. I knew that. Ok it’s 23189.” (I rock at doing subtraction in my head – blows her away every time – she checked with a calculator)
Her: “Yes. Nice one Daddy.”

This went on for a long time. She really liked the game. At some point she realized that I was not keeping score and she got mad at me. Then she realized that it would always be a tie so she said it was not a good points system. We spent some time coming up with a better points system. She came up with something. It was fairly convoluted and had to do with blue team’s ability to do an aerial cartwheel so I lost, but I’m comfortable with that.

Then I told her a story about a dude from a long time ago named al-Khwarizmi, who wrote a book called “Al-Kitāb al-mukhtaṣar fī ḥisāb al-jabr wa-l-muqābala (no, I don’t have the name of the book memorized – I always have to look it up – but I always know the al-Jabr part). I said the name of the book is a pain to say so a lot of people just called it al-Jabr. I told her that al-Khwarizmi’s book was all about ways to answer questions like the one in the game if you were not good enough to do it in your head. Take for example the clue

“If you increase my number by 7 you get 12”

al-K (that’s what his peeps called him I bet) would have said the clue slightly differently. He would have said

“Suppose thing, increased by 7 ducats, results in 12 ducats.” (take a moment to explain that ducats are kind of like dollars)

Then he would have said that you can solve it by reversing the increase, and conclude

“Therefore thing is 12 ducats reduced by 7 ducats, which is to say 5 ducats”

Then we did a few that way. I’d write “Thing, multiplied by 6, results in 18 ducats” and she’d write “Therefore thing is 18 divided by 6, which is to say 3 ducats.”

Now some people might not believe that you can ask and expect an 11-year old to use language like this, but I’ve never understood why people would think that. Speak to them this way and they will listen, understand, and respond in kind. It’s what we’re wired to do. It’s how we learn to communicate.

I should mention that at one point she asked me if al-K called his book al-Jabr because it sounds like algebra. I told her that algebra sounds like al-Jabr because of that book! That al-K invented algebra. She thought that was super cool but also wanted to know how I could know such a thing. She was amazed to find out that I studied some history in my life. Daddy points scored.

Ok. So this gets tedious right? My daughter agreed. It’s too much writing. So then I told her about a dude named Rene Descartes who really liked al-K’s methods, but was too lazy to write it all out that way. So he’d look at the sentence

“Suppose thing, increased by 7 ducats, results in 12 ducats.”

And he’d say for example that “thing” is too many letters to write, but it’s important since it’s the number we’re trying to get people to guess. So Descartes chose the minimum number of letters possible. One. I let her choose the letter. She chose “m”. She always chooses “m” when letter-choosing is the task at hand. Then I told her that “increased by” is a pain to write out also, and asked her what she thought Descartes would say instead. She wrote down “+”. Then I said what’s “results in”? She wrote “=”. And Voila! She had written

m + 7 = 12

Then without me saying anything else, she said “Oh, so then Descartes would write m = 12 – 7! Which is 5!”.

And honestly, with that the lesson was done. I gave her about 8 more equations to solve in the Descartes style, and she got them all. We never once discussed rules, and we never once switched a bloody sign.

And there were no tears.

Maybe I’ve rescued the algebra memory.

Thanks for reading,

Rich

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