Groovy Boards

Groovy Boards are a great way to show the commutative property and to show fact families. The commutative property says that "if a and b are whole numbers, then a +b = b+a" (Burris). A fact family describes the set of whole number addition facts with a common sum (Burris).

A pdf of the template for the groovy boards can be found at: http://wps.prenhall.com/wps/media/objects/1295/1326999/blackline/bm06.pdf

example of the commutative property:

The rubber band can be moved around to show ways to add to 6.

 2+4=64+2=6

Example of a fact family:
4-fact family
0+4=4
1+3=4
2+2=4
3+1=4
4+0=4
The rubber band can be moved around on the groovy board to show the different ways you can add to make 4.

 1+3=4

2+2=4