Level D: Use the terms pitch and volume to describe sound.
Level F: Describe the relationship between pitch and frequency, and between loudness and amplitude.

Explore amplitude, frequency and wavelength.

Change pitch and volume; display waveforms on a virtual oscilloscope.

See the difference in wave envelopes created by various sound makers.

Compare the speed of sound in air, water and steel.
Level E: Explain what happens when sound travels through different materials

See how sound waves travel in a solid.

See how sound waves travel in a gases.

Let air in to hear the bell; pump air out and the sound fades away.

See how a single pulse of sound travels in a solid.