Students will construct and use simple machines in two skill building activities. They will construct a complex machine which can crush a grape. Students need to provide materials for their machine. Suggestions for materials include popsicle sticks, paper cups, rubber bands, string, weights, pulley, wheels. They will then contruct a grape crusher using 3 simple machines.
Compound machines contain two or more simple machines.
The energy must be transferred from one machine to the other. Machines are designed for specific tasks and their efficiency depends on how well forces are conserved and transferred. The other simple machines, the inclined plane and wheel and axle, should be introduced in discussion, demonstration, or experiment. After developing this knowledge and skill, students will be ready to design and test their grape crushing device. The Marshmallow Catapult Lab will introduce students to levers and to the idea of energy transfer.