It's a mechanical computer that you run by sending marbles through it. https://www.turingtumble.com It comes with a comic book that tells a story incorporating different challenges that lead you through the basics of the toy to increasingly more difficult puzzles to solve. My justification is that it will be a great introduction to how computers work for my kids, sort of a pre-computer science. But the truth is, I can't wait to play with it after the kids are in bed at night!