Students make Leonardo da Vinci proud by building their own contraption from all-natural, untreated wood pieces. In 1-2 hours, students have a fully functional model that features meshing gears, reciprocating linkages, a rack and pinion gear, and a hydraulic adjustable lever that throws small objects. Inspire students to learn about simple machines, fluid dynamics, and mechanical advantage as they test their bot, and integrate math by encouraging experimentation with trajectory as they hurl popcorn at their friends. Recommended for Elementary and up. CHOKING HAZARD (1). Not for under 3 yrs.