An exciting book about the chain reaction world of Rube Goldberg for middle schoolers, including 25 engineering design projects that get middle schoolers applying the laws of physics to their own inventions as they learn the scientific principles behind the actions and reactions they create. Why use a simple hand motion to wipe your mouth when you can build a machine to do it for you? Toppling dominoes, rolling marbles, racing balloon cars, springing catapults, and whizzing zip-lines are all elements used to build Rube Goldberg machines in Crazy Contraptions: Build Machines that Swoop, Spin, Stack, and Swivel with Hands-On Engineering Activities. The book introduces kids ages 9-12 (and beyond!) to the wacky machines designed by Goldberg, which were based on complicated chain reactions used to accomplish very simple, sometimes ridiculous, tasks. * Through contraptions, the book discusses the basics of physics, including force, motion, and work. Each chapter introduces one of the six simple machines and how they can be used in Rube Goldberg contraptions--inclined planes, levers, wheels and axles, wedges, screws, and pulleys. * Kids are challenged to design, build, and evaluate dozens of increasingly complex contraptions that do things like unscrew a lid, turn the page of a book, and pop a balloon. * Projects use materials already in most homes--reimagining and repurposing everyday items, as well as mining the recycling! * Contraption hints, essential questions, short sidebars, and links to online primary resources help readers learn the basics of force, work, motion, and simple machines, while exploring their creativity as they design and build their own crazy contraptions. About the Build It Engineering set and Nomad Press Crazy Contraptions is part of a set of two Build It Engineering books that explore the engineering technology behind our daily lives. The other titles in this series is Bots! Robotic Engineering with Hands-On Makerspace Activities. Nomad Press books in the Build It series integrate content with participation. Combining content with inquiry-based projects stimulates learning and makes it active and alive. Nomad's unique approach simultaneously grounds kids in factual knowledge while allowing them the space to be curious, creative, and critical thinkers. All books are leveled for Guided Reading level and Lexile and align with Common Core State Standards and Next Generation Science Standards. All titles are available in paperback, hardcover, and ebook formats.