http://www.aaaknow.com/grade1.htm
http://www.funbrain.com/
http://www.starfall.com/
Great for practicing sight word spelling and spelling words Spellingcity.com
Great practice with the hundreds chart! http://oswego.org/ocsd-web/games/DogBone/gamebone.html
Here are some other resources that you can't find on the internet: School Library Local Public Library