Objective Students can say that sounds are caused by vibrations in things.
The teacher demonstrates that the vibration of air in a container causes sound. Fill bottles of different sizes and bottles of the same size with the same and with different amounts of water. Students predict what will happen if they blow across the tops of the bottles. The students then go ahead and blow on the bottles, trying to see if there is a pattern among the different sounds the bottles make. The students try to sequence the sounds from lowest to highest.