Solving 12 – 7 as an Unknown Addend Problem

This video illustrates how manipulatives can be used to show the relation between strategies for subtraction and addition. Students can use manipulatives and addition to find an unknown part in a part-part-whole subtraction problem. When students realize that strategies for addition may be used to solve subtraction problems, they begin to think flexibly about numbers and gain a better understanding for how number are related. 

View additional videos in the Basic Facts Series

Developed By: 
National Center on Intensive Intervention