Turn trash into invention and sharpen your engineering eye with these 15 hands-on engineering easy-to-find materials, engineer your own motor car, propeller boat, catapult, Ferris wheel, and machines. Explore amazing scientific concepts, such as potential, kinetic, and electrical energy; balances; pulleys and levers; laws of motion; and more. Each project includes step-by-step instructions, exciting facts, safety tips, and extended engineering and science activities for further discovery.