I just found this site and thought I would share it. I'm sure others already know about it but I thought it was worth sharing.
http://www.playkidsgames.com/mathGames.htmQuote from site:
Play Kids Games.com is a site designed by parents of young kids.
It is our intention is to provide a web site that parents and kids can use to learn basic skills while having fun.
It is our goal to provide a safe place to learn
computer skils, math skills, reading skills and problem solving skills in a context that is fun to use.