There's more than one way to power a toy boat. Electric motors, balloons, gears, water jets, belt drives, chemical reactions, steam, and even gravity can be used to propel a small ship across a pool. Also, the boats' propellers and paddles can be side-mounted or at the stern, or even sit above the waterline, like a fan-powered swamp boat. The Motorboat Book will show children how to build more than 20 different models through step-by-step instructions with clear photos. And if they'd rather travel under the water than over it, the book has 6 different submarine projects. In addition to the boatbuilding activities, author Ed Sobey includes instructions on how to build an “ocean” to test the boats, as well as accessories such as four different water pumps, waterproof battery and motor cases, and a working foghorn. Most of the boats are built from recycled and easy-to-find materials, but an appendix lists local and online sources for wire, plastic propellers, small motors, and more. Educators will appreciate the Meeting Science Standards summary at the end of the book.