The noted expert selects 70 of his favorite "short" puzzles, including such mind-bogglers as The Returning Explorer, The Mutilated Chessboard, Scrambled Box Top

A daily-problem format makes it easy to coach students quickly on the math skills they need for standardized tests. Includes reproducibles.

Welcome to this fantastic collection of Number Cross puzzles! Each of the numbers only has one position in the finished puzzle. Can you work out where they shou

Playing with mathematical riddles can be an intriguing and fun-filled pastime — as popular science writer Martin Gardner proves in this entertaining collectio

Here are over 300 tantalizing puzzles, brain teasers and riddles by one of the greatest mathematical geniuses of the twentieth century, Shakuntala Devi, popular