http://www.1upinfo.com/encyclopedia/
"Browse articles in all areas of topics within Earth & Environment, History, Literature & Arts, Health & Medicine, People, Philosophy & Religion, Places, Plants & Animals, Science & Technology, Social Science, Law, Sports, Everyday Life, and more..."

http://www.factmonster.com/
Fact Monster is the largest free reference site just forkids! Get homework help and find facts on thousands of subjects, including sports, entertainment, geography, history, biography, education and health.

http://www.natureserve.org/
Here is a nature encyclopedia web site. You can look up information on any plant or animal.

http://www2.worldbook.com/parents/index.asp
World Book Encyclopedia has lists for typical course of study for Kindergarten to Grade 12. Also, there is a page of 'Preschool - Readiness Skills'. A good and free resource for a "scope and sequence" type of guideline. Note that it is public-school based, and secular in nature.

http://www.letsfindout.com/
Knowledge Adventure Encyclopedia: This online encyclopedia is great for homework questions. You can browse through categories like Bugs or the Human Body, or you can search for something specific.

http://www.yahooligans.com/content/ka/index.html
Kids' Almanac: If you have a factual question, or just want to browse through some interesting information, this is a great place to start. All the contents of a good almanac, organized and written for kids!

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