This site has a Crossword Puzzle based on the book The Lion, The Witch, and The Wardrobe.
This site has a more in-depth look at the Christian symbolism of The Lion, the Witch, and the Wardrobe. It talks about the allegories used in this story.
This site has all kinds of information on the whole series, The Chronicles of Narnia. You can take quizzes, read up on the author, or learn about the characters and mythological beasts.