From: Judy (for Teacher2Teacher Service)
Date: Nov 26, 1998 at 19:05:07
Subject: Re: Checking double digit subtraction

Annamarie,  

I teach my students that since addition is the opposite of subtraction, they
need to go backwards to check. I have my students circle the answer in
question and the bottom addend. I then tell them that they are are about to
be surprised. They add these two numbers and like "magic" the top addend
reappears. It sounds silly, but they like that touch of magic.

 -Judy, for the Teacher2Teacher service

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