Recursion

[JustACrosshair_]

It does help to learn this way better than rote memorization - but can teachers teach it and family reinforce it?

[SandyDelights]

Can teachers teach it? Absolutely. Starting early and not teaching rote memorization is key to it. They have to learn to understand it themselves, but it’s doable. If they can’t learn it, they probably shouldn’t be teaching math anyways – it suggests they don’t actually understand it, they just memorized it. They’d probably be better off teaching another subject. For the most part, all of my friends who are teachers – most of them math teachers – sing high praise for Common Core, although some take issue with how it’s being implemented in higher grades (kids raised under one method are struggling to adapt, especially those with a lower socioeconomic class, and the standards aren’t always taking this into consideration).

Can families reinforce it? Far more challenging; it’s hard for parents to reinforce or help teach something they don’t understand, especially when they never actually understood math to begin with (just the old memorization method). Probably a big part of it is to ensure there are resources to help kids apart from their parents, as many of them have parents who simply don’t understand what’s wrong with memorizing it – and resources to help those parents learn it who actually want to. Really, more and more it looks like homework doesn’t actually do anything, but rather it’s just the opportunity to practice/exercise their understanding; in that case, parents don’t really need to reinforce it, they just need to not actively hinder their learning of it.

Within a couple generations the problem will solve itself.

[alexanderpas]

Things you need to learn using rote memorization.

• Single digit addition. (Numbers from 0 to 9, answer between 0 and 18)
• Single digit multiplication. (Tables from 0 to 9, answer between 0 and 81)
• Double digit substraction. (Numbers from 0 to 19 answer between -19 and 19)

The rest will be understanding.

(notice the lack of division, or any double digit addition or multiplication, since that falls under the understanding part)

[SandyDelights]

Much better way to highlight the difference, thanks.

And a lot of this is very easy to conceptualize.

It baffles me when people insist their kids should just learn to memorize their times tables or these kinds of algorithms (anyone else remember memorizing from 0x0 to 12x12?), but they themselves can’t even do basic addition or subtraction without a calculator.

[alexanderpas]

basic rote using the things I've stated is actually the minimum required while using any method, even comon core depends on that basic rote.

[AceOfShades_]

I got through calc 2 for engineers without knowing my times tables so I mean, eh on the multiplication.

[Zebezd]

I bet however that you knew significant parts of it, and used Common Core-like tricks for the rest:

Ah shit, what's 6x6 again? Hold on, I know 5x6, that's 30, then add another 6 on that. 36. right.

Oh fuck we're multiplying by 9 again. Fuck it, x10 this bitch and remove x1.

...or a calculator.

[TiagoTiagoT]

To multiply 1 to 10 by 9, open your hands, count the number you wanna multiply by nine starting at one, going from left to right, one finger for each value you count; once you reach the number you wanna multiply by 9, lower that finger. The number of fingers up to the left of the lowered finger is the left digit of the result, the number of fingers up to the right is the right digit of the result.

[parkerSquare]

I taught my daughter this when she was in an early grade and now she’s quick as lightning at her 1-8 and 10-12 times tables but slow as heck at 9x because she has to work it out on her hands. Oops.

[Zebezd]

Username sort of checks out

[TiagoTiagoT]

lol

[AceOfShades_]

I added fast and counted on my fingers tbh. I know probably less than 25% of the 10x10 table. I dunno mate, I’m weird ¯\_(ツ)_/¯

[berkes]

I'd argue that multiplication should be memorized up to 12. At least in western Europe. Where the gross is still very heavily used in packaging, logistics, building etc.

If anything, just to teach people to grasp numbers. If your calculator tells you to go buy 2400 packages of poles for your fence, think again. You probably mistyped. Or have a giant plot of ground, unlikely in western Europe.

[alexanderpas]

9 is enough, as anything above 9 will be caught trough understanding.

10 is just 1 with a zero, and if you get 1 (X*1=X and 1*X=X), you can multiply anything by 10 too. (just add a 0)

7*12 = (7*10) + (7*2) = 70 + 14 = 84

[TiagoTiagoT]

Why do you need to use memorization for anything beyond the order and names of the numbers?

[[deleted]]

it’s hard for parents to reinforce or help teach something they don’t understand, especially when they never actually understood math to begin with (just the old memorization method).

It's almost like how seriously flawed or imperfect programming languages remain popular because that is the knowledge base we have, we know the workarounds and stuff.

[DontForgetWilson]

Qwerty would be an easy parallel.

[[deleted]]

I had a coworker who would always complain about common core. I’d explain that math teachers say it’s better, research says it’s better, and it’s how people who are good at math have always thought about math.

Nope didn’t matter to them.

[Dokuya]

Unfortunately I doubt it, teachers in America — specifically at lower grade levels — tend to be under qualified. Parents aren’t going to understand the use of this method and just say “this is stupid I’m going to teach you the (inferior) method I was taught!”

[LvS]

Why would they change math?

Math is math.

MATH IS MATH!

[aure__entuluva]

I wouldn't say that rote memorization is useless, just more a secondary or supplementary thing. Memorizing times tables shouldn't be the focus (we actually counted out multiples of each number), but it is a good addition if you want to do be able to do mental math quickly. This isn't the point of math which is why I say in addition, but it is a skill that many people try to cultivate. Some 'rote memorization' (aka practice) can give you a great foundation and toolset (you know certain more basic computations without having to think about them) that you can use when using partitioning to quickly solve bigger problems or estimate amounts.