Practice game for addition
http://www.dositey.com/addsub/memoryadd.htm

http://www.dositey.com/2008/addsub/Mystery3.htm

Math Magician
http://oswego.org/ocsd-web/games/mathmagician/maths1.html

Dictionary of Math Terms
http://www.harcourtschool.com/glossary/math_advantage/glossary1.html