KenKen Puzzle Official Site - Free Math Puzzles That Make You Smarter!

"KenKen was developed in 2004 by acclaimed Japanese math educator Tetsuya Miyamoto. His educational philosophy is:

""The Art of Teaching Without Teaching.""

KenKen is a fun and addictive puzzle for people of all ages. It improves logical deduction skills while using fundamental mathematics -- addition, subtraction, multiplication and division. KenKen actively stimulates the mind, whether its use is in the home, classroom or on the beach."
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