Math Games

http://classroom.jc-schools.net/basic/math-integ.html (integer games)
http://www.funbrain.com/algebra/index.html (order of operations game — choose hard level
http://www.gamequarium.com/math.htm
http://www.coolmath4kids.com/  (has fact flash cards & games)
http://www.aplusmath.com/games/ (fact games)
http://www.funbrain.com/math/index.html (math baseball)
http://www.subtangent.com/maths/games.php (variety of concepts, including vocabulary)