Teaching Notes

You may have to help students use the drawing for For You To Do, Step 5, of the string fretted in different places. Encourage them to order the lengths they pluck from longest to shortest and look for a pattern in the pitches they observe. To facilitate ordering the pitches, encourage the students to compare the strings in pairs. After recording each result, they can readily order the pitches and corresponding string lengths.

Encourage the students to work quietly so they can observe the pitch of the vibrating string.

Students should wear safety goggles while working with the tensioned string.

Students may relate amplitude and frequency, so they would interpret louder sounds as lower in pitch. This prior conception could hinder students from recognizing that amplitude and frequency are independent variables. To help, set up a frequency generator, amplifier, and speaker. Then vary the frequency and amplitude to demonstrate that all possible combinations of pitch and volume can exist.