Here are some great math links for all kinds of interesting math:
Videos about any math subject from addition to calculus.
Math skills and logic puzzles for elementary and middle school students. Also some fun ways to practice multiplication and division facts.
Pre-algebra from another dimension. An interactive math problem solving game.
Math Maven Mysteries
Math mysteries that are engaging and colorful. Check it out!
Lots of games for K-8, practice with facts and story problems
Overall website for math concepts: