Hands-on science is the best way to learn. Elenco's Snap Circuits: Motion Detector kit provides the circuits needed for kids to build a working motion detector along with six other projects that include a police car, fire engine, machine gun, European siren, and more. Projects build off of the first, most complicated model with only slight deviations. The initial construction directions include a graph and step by step directions. Ages 8 & up.