http://www.primarygames.com/Number%20Game/start.htm

http://en.wikipedia.org/wiki/Numbers_game

http://www.masslottery.com/games/numbersgame.html

http://www.primarygames.com/math.htm

http://www.funbrain.com/kidscenter.html

http://en.wikipedia.org/wiki/Number_(game)

http://education.jlab.org/nim/index.html

http://www.answers.com/topic/numbers-game

http://www.funbrain.com/numwords/index.html

http://kids.niehs.nih.gov/brnumber.htm