Here are some websites to practice addition:
http://www.coolmath-games.com/0-feed-fribbit-addition/index.html
http://www.mathplayground.com/ASB_AlienAddition.html
Here are some websites to practice subtraction:
http://www.coolmath-games.com/0-feed-fribbit-subtraction/index.html
http://www.coolmath-games.com/0-feed-fribbit-addition/index.html
http://www.mathplayground.com/ASB_AlienAddition.html
Here are some websites to practice subtraction:
http://www.coolmath-games.com/0-feed-fribbit-subtraction/index.html