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Re:Math education: It’s not about numbers, it’s about learni... by watwut on Tuesday July 11, 2017 @02:00PM (#14746401)
Memorizing time tables and similar rote learnign means that precisely kids who could be good at math hate it. Meanwhile, those who have good memory and sux at problem solving think they are good at it.

People who were taught by memorising go into outrage a new type of exercise is introduced. Suddenly thinking is needed and that is bad in their eyes. Not exactly success. Meanwhile, you can memorize time tables in later age if you decide it is useful (people rarely do).

Re:Math education: It’s not about numbers, it’s about learni... by throwawayjava on Tuesday July 11, 2017 @05:19PM (#14748179)
I think this is a very astute observation. I know a lot of people who develop problem solving skills later in life after realizing that their mathematics education in high school was woefully inadequate. I don't know anyone who memorized a multiplication table by choice, and I know several professional mathematicians/engineers who haven't memorized their 10x10 or 12x12 multiplication table.

Once people see what they need out of mathematics for success in life, they never choose to memorize multiplication tables. But they do often learn new problem solving techniques.

That should tell us something about which is more important.

(But of course, we don't have to choose between the two either.)

Re:Math education: It’s not about numbers, it’s about learni... by alasdair_ on Tuesday July 11, 2017 @07:44PM (#14749045)
I never managed to memorize my times tables. I never managed to memorize other formulae either, which meant that in an exam without a cheatsheet I'd have to do things like draw a bunch of triangles, measure them (graph paper) then re-derive the Pythagorean formula that I vaguely remembered involving a square root.

It sucked.

Re:Math education: It’s not about numbers, it’s about learni... by sethammons on Wednesday July 12, 2017 @10:46AM (#14752932)
Blind memorizing is a problem. Memorizing things that you have learned concepts behind makes a student faster. As an example, the way I've taught my kids multiplication starts with: let's count by 2s! Great, now you know that, let's do 3's! 4's, ... 12's. We got to the point where we could count fluently (speed + accuracy), and incorporated fingers to help. Then we started saying things like, "if we count by fours five times, what do we get?" and then we changed our words to "four times five." All my kids have done well so far with this method. There is some memorizing to become fluent, but it is fully backed by understanding.

The next steps are to start doing things backwards, "how many times do we count by four to get to twenty?" And we start to introduce notation. Bingo, simple division. This leads directly to simple fractions. This opens up conversations on adding and subtracting fractions, then multiplying and dividing them.

My oldest kid, now in college, could add, subtract, multiply, and divide fractions by second grade and understood them. Oddly, she had a horrendous time learning decimals. Her mental model of numbers was fractions and decimals were "weird." She would have to change things like 5.045 to 5 45/1000 to understand it, and wanted to work with it as a fraction. It took a long time for her to get comfortable working with decimals.

One time that I think it paid off. I told her that 0.999... is equal to 1. She said false. I said, no, it is true. Can you tell me why? At this time, she was in algebra, and I was expecting to show her how to prove it using algebra. She had a much better way of looking at it. In about a couple of seconds, she said, "well, 1/9 is 0.111... and 9/9 would be 0.999... and that is also 1." Her answer was much better than mine. :)

An example of when memorizing is bad (ie, when the underlying knowledge is skipped) was her 7th grade algebra teacher. In teaching the laws of exponents, he said "anything to the 1st power it itself and anything to the 0th power is 1. We don't know why, it is just one of those math things." Teaching like this is why we have students who, later in high school, can't do x^0 or x^1 because they think, "it is either 1 or 0 or itself, I don't remember." As opposed to applying mental models and patters to see that 3^3 -> 3^2 -> 3^1 -> 3^0 is just dividing by 3 each time. These students know 3^2 is 9. So they should know that the next is 9/3 = 3 and that the next is 3/3 => 1.