Book excerpt: Build a nearly two-foot-tall marble run, and learn all about the scientific principles behind your creation with this interactive science book and kit. This is no ordinary maker kit. It contains everything kids need to build a nearly two-foot-high working marble run, complete with wheels, ramps, stops, and drops—two marbles included. As construction begins, young engineers in training can read along in the accompanying 64-page science activity book to test theories, perform experiments, and learn all about mechanics, speed, forces, and other scientific principles that relate to their marble run. Focusing on STEM concepts in a fun and engaging way, this kit is a great option for an upcoming science fair or a quiet rainy day at home.