FunBrain is a popular site for online educational games for kids of all ages (math, grammar, science, spelling, history)
Features fun and educational resources for kids with games, animals, music, jokes, movies, news, astrology and more
Great Reference Site for Grade 2
New Book Of Knowledge (Part of Groiler Reference)
This is an encyclopedia that is for Grades 2-5. This link will take you to the main Groiler Reference Page, then click on New Book Of Knowledge.
Search engine for general information.
National Geographic for Kids
All kinds of information on nature and animals.