You don't need to be a genius or a professor of mathematics to have hours of fun with this book - just some logical thinking, a little common sense, a bit of ge

Take the Mensa challenge! These extraordinarily entertaining puzzles can confound even those with high IQs-and that's what makes them such delightfully tricky f

Here are enough tough puzzles to test your mental powers for hours and hours. Try this never-ending array of puzzles, challenges, funky facts, things to build,