The Invention Hunters travel the globe in their flying museum collecting the world's greatest inventions Today they've landed in a construction zone. These silly scientists think they've stumbled on incredible specimens of everything you'd never find at a building site, from roller skates and pogo sticks to swords and race cars. But what they really discover--with a kid as their guide--is how simple machines like pulleys, cranks, and levers are used to engineer tools ranging from jackhammers to dump trucks...and even toilets

Using simple explanations and diagrams and a heaping helping of humor, the Invention Hunters make the perfect companions for curious kids who are ready to learn about science, physics, engineering, history, and more.