Puzzlers can have challenging fun every day of the year with 365 problem-solving exercises to test and sharpen their skills. Numbers, words, logic, concentration, creativity: they're all worked out. Puzzle icons at the top of each page explain exactly which ability is being tested and the difficulty level. Look at a diagram and figure out how many square and rectangles it would have if the diagonal lines were removed. Arrange a block of text alphabetically to find out what the 13 word would be. Complete a magic square so that it contains all the numbers from 1 to 25, and so that the sum of each line, column, and the two diagonals come to 65. These mental gymnastics will definitely keep the mind in top shape.