Build Your Own Chain Reaction Machines

December 1, 2018
Grades 5-9 While chain reaction machines are not useful, they are definitely fun to build and watch. A brief introduction describes how these complicated devices perform mundane jobs by linking a series of simple tasks (e.g., deflating balloons, releasing marbles, and springing mousetraps) to produce a domino effect. It also notes that these outlandish contraptions are sometimes called Rube Goldberg machines, after the inventor and cartoonist whose depictions made them popular. Following a chapter on basic tools and techniques (e.g., making washers, gears, and perfect circles), the book dives into building 13 chain reaction machines, from light switcher and plant waterer to marble launcher and cookie dunker. Each profile comprises materials needed (all easily accessible from home-repair stores) and detailed, step-by-step directions, which are also complemented by high-quality color photographs. In addition, the explanations include sidebars with troubleshooting tips and Engineering Know-How, which relates the science used, such as force, gravity, resistance, and counterweight, to form the chain reaction. The author leaves plenty of room for experimentation as well in this ideal resource for maker spaces.(Reprinted with permission of Booklist, copyright 2018, American Library Association.)