Internet Public Library

Even has resources for toddlers!

http://www.ipl.org/div/kidspace  

Surfing the Net with Kids - Fun Educational Games

http://www.surfnetkids.com 

Award-winning Educational Games and Apps 

Created or approved by certified teachers.

http://www.abcya.com/ 

 Funbrain, created for kids ages preschool through grade 8, offers more than 100 fun, interactive games that develop skills in math, reading, and literacy. Plus, kids can read a variety of popular books and comics on the site, including Diary of a Wimpy KidAmelia Writes Again, and Brewster Rocket.

http://www.funbrain.com

AAA Math features a comprehensive set of thousands of interactive arithmetic lessons. 

http://aaamath.com

 Over 300 FREE interactive games and activities from TES iboard.

http://www.tesiboardus.com

Kaboose FunSchool- Family fun from Pre-K to 5th grade

http://funschool.kaboose.com 

Lots of fun math games.

http://www.mathplayground.com