Materials that transmit sound

In the middle and senior classes children will develop their understanding of the nature and properties of sound. Many children think that sound travels only through air. They will be guided to discover that sound can travel through solid substances, gases and liquids. They can make string telephones to demonstrate that sound travels through solids.

The children can discover that liquids such as water transmit sound by listening to the fizzing sound of an Alka-Seltzer tablet that is placed in water. Other materials, such as wooden dowelling, metal rods, plastic and copper piping, can be investigated for their effectiveness in transmitting sound.