I'm a math teacher and tutor, and I find most math puzzles and recreations to be a little academic at best, and needlessly obscure at worst. The exercises in Gardiner's book, however, are rich in useful mathematical ideas, and each question builds on previous ones in the chapter. After playing with these puzzles, the student (and teacher!) will be able to apply what they've learned to other math questions. Everything from number theory to geometry is touched upon in these challenging, thought-provoking excursions for the mind.