Gifted Issues Discussion homepage Forums Parenting and Advocacy Is This A Red-Flag?

Okay, the rigid setting out requirements, and the remedial level, are ridiculous, I agree. But it is worth understanding the idea of solving

5026-
2819
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by thinking of it as

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5026

Coming back to this to update.

At the PTC, the teacher surprised us by showing an end-of-year test she gave DS for third grade math. He scored 72% correct. She said it was impressive (he answered a question on perimeter correctly) and thanked us for bringing to her attention a couple weeks before that he needed to be tested to determine if he could could move up. So, as of yesterday, DS has been moved from second grade math to third. He's finally going to run up against things he doesn't know, and he's excited!

As for his shouting out answers as being her hesitation in moving him into third grade math, she said he's shown acceptable restraint since we talked and that wasn't a factor any longer. I was glad to hear that!

It was like a weight lifted off my shoulders when she pulled out that end-of-year test. I thought I was going to have to bring the whole subject up again. It was a pleasant surprise.

It would be better if she admitted that it never should have been a factor in the first place.

That's really great. Congrats on that.

Yes and no. The concept is obviously important, so yes in that regard. But it's simple idea that doesn't need to be taught using four-digit numbers. It can easily taught by turning 8-3=? into 3+?=8. In this case, the concept is very easy to see because the calculation will be obvious to most students. Thus, they can focus on the addition concept without getting trapped in the details of the calculation (in which case they may not see the forest for the trees). So no in that regard.

As Master of None said in another thread, educators seem to find ways to fail. IMO, this is one of them: take a straightforward concept that can easily be demonstrated by one-digit fact families or on a number line, twist it, and create something capable of confusing an engineer or a scientist.

No. It is not just that a-b=c is equivalent to b+c=a. The point is also that you can use this to find a difference, but using what you know about finding sums. And this is clearly different for 4 digits than for 1 digit. It gives a more efficient and natural algorithm for multidigit subtraction than the grotesque method typically taught in American schools.

This is definitely not an example of what master of none was referring to here.
http://giftedissues.davidsongifted....icle_on_ability_grouping.html#Post175845

No, it's the same for 4 digits and 1 digit. That's a major point in mathematics: concepts aren't different, don't change or fail to apply because you use different numbers. It has to work every time or it's wrong.

If you're referring to subtraction with regrouping, I'm not sure why you're calling the standard algorithm grotesque. However, I do know that many folks without a solid understanding of mathematics and how its pieces fit together often mistakenly believe that the standard methods are somehow bad and should not be taught. There is a LOT of misinformation out there. I recommend reading this paper by a mathematician from UC Berkeley. He does a good job of explaining why misunderstandings arise. He also discusses the importance of the standard algorithms and how they fit together in the broader tapestry of mathematics.

It's a bit like you're saying that a red triangle is the same thing as a red circle because they are both red. You are ignoring the obvious difference.

Okay, when people respond with a straw man, I know it's time to quit.

What?! 4 digit arithmetic is not the same as 1 digit arithmetic. When it comes to designing an algorithm to actually do the computation, the multi-digit case requires extra concepts. The difference is real.