Here are some great websites that will give you some practice in various subjects!
http://www.aaamath.com
http://www.factmonster.com/homework/hwmath.html
http://www.mathplayground.com/index.html
http://www.multiplication.com
http://www.abcya.com
http://www.earobics.com/gamegoo/gooey.html
http://www.eduplace.com/kids/hme
http://www.wordle.net
http://www.funbrain.com/
http://www.tagxedo.com