Good simple machines to build for a student project include a jumping bean lever, an inclined plane ramp, and a pulley system. Additional simple machine projects include a simple wheel-and-axle machine and an Archimedes screw.
The jumping bean lever is a project that shows how a lever can change the size and direction of a force. Materials necessary to make this project include a ruler, a Popsicle stick, a large dry bean and a pencil or marker.
An inclined plane ramp project demonstrates how it is easier to use a ramp than to climb straight up. Materials necessary for this project include a stack of books, a board, string and a ruler.