Summary Introduce forces and how they are passed from one object to another with the coin game. Then jumping stick or catapult to show chains of forces passing between different materials. Air resistance a surprising force with good discussion. Science content Physics: Motion and Forces, Newton’s Laws, Gravity (K, 2, 6) Physics: Energy forms, Conservation of Energy (1, 3, 4, 5) Activities in this lesson Coin game Jumping stick Catapult - torsion Catapult from tin can / poster tube Air resistance Procedure Forces make things move, or make moving things stop. Another name for a Force, which is easier to envision, is a Push or a Pull. Start with coin game, either as a demonstration (on a hardcover book) or for students to do at their desks. Focus students on where the force is actually happening - between the finger and coin, or between coins, as they touch. Friction slows the coin down as it slides on the surface. Summarize that there is a chain of forces that make the coins move then stop. Another chain of forces in a jumping stick toy or a catapult. Grade 2 and up can make jumping stick Primaries can make torsion catapult (adult assistance needed for youngest grades) Grade 2 and up can make a more powerful tin can catapult (adult assistance needed for primaries) Allow free play and optionally measuring and recording of distances, before regrouping to discuss the specifics of the chain of forces. Forces make the parts move, and also make them eventually stop. End with counteracting forces: We have seen that forces make things move, and that forces make things stop. The balancing of opposite forces determines whether something will stop or slow down. When something slides along the floor, the forward movement is balanced by the friction against the floor. When something is falling the force of gravity is balanced against air resistance, pushing up against the object. Air resistance activity with the two paper plates works well as a demonstration with discussion. Grades taught Gr K Gr 1 Gr 2 Gr 3
