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Many elementary teachers don’t understand math, and it makes them anxious

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Re: Many elementary teachers don’t understand math, and it makes them anxious

#81
post #35

Earlier quoted context omitted.

You're never going to find 100 people who can perform long division.

Sure you can! Just look at a typical fifth- or sixth-grade classroom. Most of them can perform long division, briefly, before the test. They may even remember it for several days after the test.

What none of them can tell you is why they've been taught long division, when short division is faster.

And it's because you need long division to do division in algebra

Re: Many elementary teachers don’t understand math, and it makes them anxious

#82

I have a hard time explaining to my children how addition of fractions work. Not how to do that, but how to feel the intuitive way. And percentages, to some extend. The sad part is that I have a PhD in physics and an engineering degree in CS. I used to teach physics at the uni and loved it. My children like me to explain them physics because I love it so much and they appreciate the analogies, their limits etc. It is…

If you want to add 2/3 + 1/4 (=11/12), take three square sheets of paper. Call the area of each one.

1. Cut the first sheet into 3 equal parts. Take 2 of them (labelled A and B) and place them side by side on the third sheet.

2. Cut the second sheet into 4 equal parts. Take 1 of them (labelled C) and place it on the third sheet next to the other two pieces from part 1.

3. Now, figure out how much area the three pieces cover of the third sheet of paper. If you do it right, you can cut the third sheet of paper into 12 pieces, such that the 11 of these pieces will cover A, B and C exactly.

Sometimes you will need a fourth sheet of paper in case the sum is greater than 1.

There are many variations of this. You can pour 2/3 of the water from one 100 ml graduated cylinder and 1/4 of water from another 100 ml graduated cylinder into a third one. Or use sand and weight it. If all numbers are divisors of 12, you can use the clock.

Re: Many elementary teachers don’t understand math, and it makes them anxious

#83

I have a hard time explaining to my children how addition of fractions work. Not how to do that, but how to feel the intuitive way. And percentages, to some extend. The sad part is that I have a PhD in physics and an engineering degree in CS. I used to teach physics at the uni and loved it. My children like me to explain them physics because I love it so much and they appreciate the analogies, their limits etc. It is…

Just get a few measuring cups and some water. Half a cup and a quarter cup makes three quarter cups, because really, half a cup is two quarters of a cup.

Re: Many elementary teachers don’t understand math, and it makes them anxious

#84
post #2

I still don't know why long-division works. I don't think I even remember how to do it as an adult. I've always had a very intuitive grasp of math, which meant I excelled at solving things in my head but struggled with (and resented) having to show my work in the arbitrary algorithms we were taught. I understand division despite my education. They really should try to come up with algorithms that are more intuitively…

You should probably read about it as an adult: https://en.wikipedia.org/wiki/Long_division Children are mostly idiots. Education is the process of painfully breaking them out of their idiocy. Bonus points if you implement a long division algorithm that works on strings in your favorite language.

After a brief glimpse at that page I am glad we were taught the Eurasian method. I had no problem with it.

Re: Many elementary teachers don’t understand math, and it makes them anxious

#85
post #44

If we are serious about trying to "break the cycle", one obvious solution is to pay teachers more. Imagine if teaching paid as well as software development.

> Imagine if teaching paid as well as software development.

I’d love this personally. But the organizations that employ teachers do not make the same amount of money, per employee, as organizations that employ software engineers.

Depending on your state, your property taxes would need to double or triple to make the math work out.

To be clear: I’m not making a comparison of the value provided, just the accounted-for profit. Society as a whole would obviously benefit from exceptional math teachers at every school, but we would need to get creative to pay for it. Perhaps we should be spending less on wars.

Re: Many elementary teachers don’t understand math, and it makes them anxious

#86

Huh. I'm from India, and from what I can tell, maths is taught much better here than in the US, at least till 10th grade, after which it's no longer compulsory. It's actually taught in a very intuitive manner, and most students "get" it quite well. Edit: the textbooks are freely available on the web, if anyone wishes to take a look. Look up "NCERT class 10 maths textbook".

My experience has been the opposite. Indian kids can solve math problems in the "curriculum" quite well but ask them to do anything WITH the math and they're lost. Ask them how the theorem relates to the natural world and they don't know. Ask them what applications it has and they don't know. Ask them to extrapolate their current knowledge base to a theoretical future and they are completely lost on what a "next step" would look like.

Information is laser focused on getting into an "Engineering college" and not actually on "knowing" anything. It's like teaching someone about spoons and forks but never giving them any food to actually interact with but vaguely mention "food will be relevant when you get a job, not right now"

Better than american kids sure but i'm not sure anything more of value is earned by making these kids essentially memorize theorems and algorithms

Re: Many elementary teachers don’t understand math, and it makes them anxious

#87
post #83

I have a hard time explaining to my children how addition of fractions work. Not how to do that, but how to feel the intuitive way. And percentages, to some extend. The sad part is that I have a PhD in physics and an engineering degree in CS. I used to teach physics at the uni and loved it. My children like me to explain them physics because I love it so much and they appreciate the analogies, their limits etc. It is…

Just get a few measuring cups and some water. Half a cup and a quarter cup makes three quarter cups, because really, half a cup is two quarters of a cup.

Which is all well and good... Until you need a half of a quarter (which I'd use tablespoons for as there are 16 tablespoons in a cup), a half of a third of a cup, or need to add 1/3 and 3/4 together.

Which isn't so bad for a recipe because most things aren't that precise in cooking - but not so easy for all students to work out, especially without having a tablespoon to use. This is even so when you have tablespoons: Those 1/3 cups don't divide neatly into tablespoons.

That said, it isn't like you cannot illustrate it, of course, but just that this method isn't the best. I've just memorised the cooking stuff since I only have a 2-person household.

Re: Many elementary teachers don’t understand math, and it makes them anxious

#88
post #42

Earlier quoted context omitted.

That seems like a stretch.

University of Chicago study for you to peruse https://news.uchicago.edu/story/female-teachers-can-transfer...

Even assuming the study holds up, that doesn't mean that only the girls picked up the fear. It means only the girls were affected by the fear, by overly generalizing from this one example.

Re: Many elementary teachers don’t understand math, and it makes them anxious

#89

Huh. I'm from India, and from what I can tell, maths is taught much better here than in the US, at least till 10th grade, after which it's no longer compulsory. It's actually taught in a very intuitive manner, and most students "get" it quite well. Edit: the textbooks are freely available on the web, if anyone wishes to take a look. Look up "NCERT class 10 maths textbook".

Why do you think math is taught much better in India?

Re: Many elementary teachers don’t understand math, and it makes them anxious

#90
post #81
post #35

Earlier quoted context omitted.

Sure you can! Just look at a typical fifth- or sixth-grade classroom. Most of them can perform long division, briefly, before the test. They may even remember it for several days after the test.

What none of them can tell you is why they've been taught long division, when short division is faster. And it's because you need long division to do division in algebra

What is short division? I only remember being taught long division and having a calculator. Is there another method?
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