Wednesday, November 9, 2011

Subtraction Trick

This is a great modification for students who have difficulty with these types of problems.  Students simply rewrite the problem using the numbers that come before the original numbers in the problem.  They may then subtract without the difficult regrouping process necessary in problems with all of these 0s. 

Add this method to students' repertoire.  They'll think they're getting away with something and you'll get lots of subtraction practice.  You may even want to split the class in half and have a subtraction challenge:  half the class uses the traditional method while half the class tries the subtraction trick.  Check answers and see how accurate each group is.  Allow students to choose the method that works best for them.

1 comment:

  1. What a great idea! Will definitely use this for some of my kids>