http://www.mathplayground.com/multiplication05.html

http://www.softschools.com/math/subtraction/3_digit_subtraction/3_digit_subtraction_with_regrouping/

http://www.aplusmath.com/Games/index.html

https://www.ixl.com/promo?partner=google&campaign=1147&adGroup=Non-bounce+1-14&gclid=CO2mnYKw18gCFdiRHwodlQsDcQ

http://www.coolmath-games.com/1-complete-game-list

http://www.coolmath4kids.com/

http://oswego.org/ocsd-web/games/mathmagician/mathsmulti.html

http://www.math-play.com/4th-grade-math-games.html  

http://www.math-play.com/multiplying-decimals-game.html  (multiplying decimals)

TenMarks
https://www.tenmarks.com/login

Think Central - Go Math Animated Models
http://www-k6.thinkcentral.com/ePC/studentClassProducts.do