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. If the students are interested, they can make a water marimba. Fill several same-size drinking glasses with water at different levels and strike lightly with a wooden spoon or stick.
Students discuss high and low tones in relation to the amount of water in the identical containers.