Here are great links for students:

Online Activities 

• Brain Pop

• TumbleBooks

• JunkBot

• Funology  activities for K-6

• Fun Brain activities for K-8

• Alfy.com good for k-2

• Crayola Activities

• netTrekker

• Strategy Games

• How Stuff Works

• Awesome Clip Art for Kids

• Boowa & Kwala

• Bones Puzzle

• National Gallery of Art