Fun, but it's just puzzles
Several of the puzzles are classics, like getting farm aminals across a river in the right order. About half the puzzles take advantage of being in an electronic form with a stylus, but there are a whole lot of pen and paper word problems too. Most of the puzzles are straight forward, but there are a few that are a little ambiguous. This will drive a hardcore gamer crazy. It's really frustrating to lose some points because the wording of the puzzle is not clear.
Outside the puzzles you can do pixel hunts to find coins and more puzzles. The game has a great interface for solving a jigzaw puzzle, but there is only one jigzaw in the whole game, and you find the pieces slowly throughout the game. The animation is nice, and the full video cartoon cutscenes were impressive compared to other DS games. So, overall, it's a good waste of time. Oh, and if you didn't take any Computer Science Graph Theory courses in college, you should pick this up to learn a little of it.