A whimsical collection of mechanical puzzles, riddles, mazes, provocative problems, and more is accompanied by a host of hints to help readers solve the puzzles, an easy-reference answer page, and hands-on materials.
Another book I picked up when I was designing my puzzle curricula. I like Klutz books. There's some good stuff in here. Most of it, however, was above my students' abilities. Good stuff, nonetheless.