In an outdoor setting, have each student hold a basketball above the ground. Ask students if the basketballs have energy when they are just holding them. Students should answer that they do not. Explain that the basketballs do have energy, because they are being pulled toward the ground by gravity, but because their hands are preventing the balls from falling, they only have potential energy. Tell students to drop the balls and let them bounce back into their hands two or three times. Explain that when they removed their hands, potential energy was converted into kinetic energy as gravity pulled the balls toward the ground.
Tell five students to stand in a row on one end of a large area, such as a gym or outdoor basketball court. Have five other students stand on the opposite end. Tell both groups to slowly walk toward each other until they meet in the middle. While they walk, tell them to look at the other people in their row and at the people in the other row. Ask if the people in their own row and the other row seem to be moving. They should answer that those in the same row do not seem to move, but those in the other row do. This is because kinetic energy is relative to the observer. If two bodies are moving in the same direction, they will not seem to move at all, but if they are moving toward each other, they will seem to get closer and closer until they collide.
Ask students how they think their body moves. Tell them to write a paragraph on this question and ask for volunteers to give their answers. Have a volunteer come to the front of the room to demonstrate several simple actions, such as raising his hands up and down or holding a book. Explain that chemical energy in the form of food becomes part of their bodies when they eat. When they want to move, their brains send their muscles a message to use up some of the chemical energy to make the muscle contract, creating kinetic energy.
Ask students to write a paragraph giving different ways that kinetic energy is converted into other forms of energy, and have volunteers share their examples. Tell students that the most common method of creating power is the turning of the turbine, which uses magnets to creates an electric current. Tell students to come up with and draw pictures of potentially untapped sources of kinetic energy that could be used to generate electricity in the future.