A model of an eardrum helps children, especially visual learners, learn how the eardrum works. To create the model, stretch a piece of plastic wrap tightly over a large bowl or pot. Place 20 to 30 grains of uncooked rice on the top of the plastic wrap. Hold an object that will make a loud noise when hit, such as a cookie sheet, close to the plastic wrap. Bang the cookie sheet with a spoon to cause the vibration of the sound to move the rice. In this demonstration, the plastic wrap represents the eardrum, which vibrates at the sound of a noise or tone and sends a message to the brain.
Play a game of identifying noises while blindfolded. Have the students bring to the classroom various items that make distinct sounds. Items can include coins to jingle in a jar, paper to crumble, a ball to bounce, a book to close or water to drip. Blindfolded students take turns identifying the item making the noise.
Second grade students can make music while learning how the vibration speed affects the pitch of a sound. For this project, fill five or six identical glasses with different amounts of water. The glass will vibrate and produce a sound when tapped with a metal spoon. The glass with the least amount of water will vibrate the most, resulting in the sound with the highest pitch. The vibration rate lessens with the glass with the most water, which produces a lower-pitched sound. Students can try playing songs or compose their own music while tapping the collection of glasses.
This activity will demonstrate how human vocal cords produce sound. Each student or group works with a drinking straw, a narrow rubber band, a wide rubber band and a plastic cup. Stretch the rubber bands and place each one around the cup vertically to cross the mouth of the cup. Demonstrate the different sound produced while plucking each rubber band. Next, have one student blow through the straw onto the rubber bands while another student plucks the bands. Discuss how the air changed the sound they made and explain that the air passing through the rubber bands mimics the way vocal cords work.