US students are usually weakest in fractions, so be sure to practice those games below when you are on your own.

http://www.aaamath.com

http://www.math-play.com

http://www.sparkchess.com

http://www.funbrain.com/brain/MathBrain/MathBrain.html

http://www.watchknowlearn.org

http://www.coolmath.com

http://www.arcademicskillbuilders.com