The Number System Apply and extend previous understandings of operations with fractions to add, subtract, multiply, and divide rational numbers.

http://www.mathgoodies.com/lessons/vol5/multiplica...

http://www.themathlab.com/toolbox/algebra%20stuff/...

Now we will use the program from Mangahigh

You will type in URL address with school code along with user name and password

http://www.arcademics.com/games/integer-warp/integer-warp.html