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Why do we still teach people to calculate?

freakonomics.com

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Re: Why do we still teach people to calculate?

#42
post #14

Yes we should start my six year old with group theory. When we go to the farmer's market I can ask him under what transformations is an apple invariant, and then pay for it by having him solve a Rubiks cube.

You joke, but it's become a thing for kids to do Rubik's cube. I think it's great for algorithmic thinking. My kid has a whole bunch of classmates who spend their time cubing, going from one algo to a more advanced one, discussing with their friends.

Re: Why do we still teach people to calculate?

#44

Because being able to do basic order-of-magnitude arithmetic in one's head is a critical thinking tool essential to detecting nonsense claims in real time.

It’ll also help you from getting ripped off, whether that’s a cashier mistakenly giving you the wrong change or friends calculating a restaurant split in their favor, or a malicious business trying to screw you over (banks!). Mental arithmetic is vital to mental self defense.

Interesting how malice is implied in the safest circumstances and mistake in the most hostile in those examples.

Re: Why do we still teach people to calculate?

#46

He is making a really long winded point I'm not sure I completely understand, so feel free to correct me if I am off here, but I could not really disagree more. While there is value in emphasizing things like defining/abstracting a problem rather than calculating the result of it, things like the "algorithm" typically taught to elementary schoolers to do long division is pretty much how you would naively/algorithmica…

This is why I think we'd be better off doing a load of olympiad questions. Those are exactly the kind of thing where you can practice the flash-of-insight type thing that often gives an elegant solution.

Re: Why do we still teach people to calculate?

#47
post #18
post #2

Because you need to be able to run numbers in your head for a lot of practical tasks, and inability to do napkin math can cost you very dearly

This isn't just folk wisdom either. There's an active subfield of cognitive science that focuses on working memory/cognitive load and math instruction. Broadly speaking, it's hard for students to successfully transition to even basic algebra if they don't have basic calculations down.

It's all about building higher and higher abstractions. Arithmetic - > Algebra -> higher order algebraic algorithms.

For example, when I taught differential equations, my non-scientific observation was that otherwise smart students struggled more with getting the algorithms down, if they struggled with algebra. Having to constantly jump down to a lower level of abstraction while performing the algorithmic steps is what caused confusion to mistakes.

Re: Why do we still teach people to calculate?

#48

Earlier quoted context omitted.

> Mathematicians are very much in davis/hersh "what is mathematics anyway" This reminds me of getting my CS degree in the early 2000s, then slowly realizing that my comp-sci program had taught me lots of interesting things about how computers and programs work, and essentially nothing about how to write code for a living. Also reminds me of playing Dominion (the card game) with another student, me saying "Okay, I've…

I got my degree in the mid 90's and let me tell you - high school guidance counsellors in the 1980's had no clue at all what computer science was. I arrived at university expecting to be writing a lot of programs and was soon struggling with a heavy load of mathematics and proofs. Our introduction to computer programming professor made it clear that that class was the only one where we would be taught to program. Com…

The problem with actually learning to code in school is that you'd spend a lot of time learning specifics that become outdated, which you could've self-studied anyway. Idk what it was like in the 1980s, but in 2015 our CS practice problems and tests were mostly pencil+paper, with actual code only used as a teaching tool in projects and some homework (more in lower divs).

Re: Why do we still teach people to calculate?

#49
I think that learning some basic by-hand computation skills is useful. The question is where do you draw the line. The current practice seems to be to stop at long-division. To me this seems a reasonable place to stop. There are hand methods to do more complicated calculations, such as computing square roots, that are not taught in school, which is probably fine. I don't think leaving out long-division would save that much time, and I think it's a good mental exercise for kids to have to learn a fairly complex algorithm. If I could suggest one improvement, it would be that in later advanced math courses, they returned to long-division and explained at a deeper level why that algorithm works.

Re: Why do we still teach people to calculate?

#50
post #3

It's interesting to discuss mathematical literacy with primary school teachers, mathematicians, statisticians, data scientists. I do periodically. Primary school teachers respect core fundamentals as kids acquire "mental muscle memory" and realize they have to both create some axiomatic knowledge (axiomatic in as much as you know 9x9 is 81 from rote recall, not because of a belief in inductive reasoning) as well as t…

While I can agree that in the later years, the math becomes unnecessarily prescriptive, as a mathematician myself, I am categorically not in the 'what is mathematics anyway' camp, at least not for kids.

For children, it is fundamental that they calculate. Learning arithmetic is the first introduction into the idea of infinity, which is a vital concept all children must come to terms with. The natural numbers pop up everywhere and is a basic life skill.

Mathematicians and philosophers can pontificate later as to what the exact nature of mathematics is, and if the real numbers are actually real, but none of that means that kids shouldn't learn how to count.

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