http://schools-wikipedia.org/
This 2007 Wikipedia DVD Selection is a free, hand-checked, non-commercial selection from Wikipedia, targeted around the UK National Curriculum and useful for much of the English speaking world. It is about the size of a fifteen volume encyclopaedia (24,000 images and 14 million words)
http://simple.wikipedia.org/wiki/Main_Page
Main Page - Simple English Wikipedia, the free encyclopedia
http://www.pantheon.org/
Encyclopedia Mythica: mythology, folklore, and religion. The mythology section is divided to six geographical regions: Africa, Americas, Asia, Europe, Middle East, and Oceania. Each region has many clearly defined subdivisions that will ease your search. The Folklore section contains general folklore, Arthurian legends, and fascinating folktales from many lands.