borrowing in subtraction... the top number needs to be bigger. help!

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We are on to division and M still forgets that the top number needs to be bigger in long subtraction!

Any videos, catchphrases, ideas?

Thank you.

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oops never mind, I missed the division part

Edited by stripe
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Thanks for all of your help!

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I told my son that the top number needs to fight the bottom number. If the top number is not strong enough, he needs to get help from the guy next to him. My son got it right away.

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We are on to division and M still forgets that the top number needs to be bigger in long subtraction!

On an abacus, I would put 8 beads to one side. "Can you find a [group of] seven hiding in that?" He would move seven aside. "And how many are left?"

Again with 8. "How many groups of three are hiding in that?"

Etc.

Then do it with dice, then with written numbers.

This was both an intro to division and subtractability.

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More on the top, don't stop.

More on the floor, go next door.

I tell my students to say each number before deciding until it becomes more automatic.

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Well, I almost hate to suggest it, because I had a kid who did not do well with 'borrow' as a phrase...but I know in the local ps they teach the kids "Bigger Bottom Borrow" as a catch phrase.

Some kids do fine with the phrase 'borrowing' instead of 'regrouping' and if so, this can be a nice reminder.

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More on the top, don't stop.

More on the floor, go next door.

That was the one I was trying to remember!:)

I do have an abacus too. Kalanamak. Thank you!

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Legos. Collect a pile of 2x2 bricks to make stacks of tens with. Keep about twenty loose for the "ones." Have him act out every single problem until it's automatic, and he can explain why in his own words. :)

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