1.1 Sound and music activities  (Page 4/5)

Discussion questions

• If using bottles of different shapes and sizes, how does the size of the bottle affect the pitch/frequency? Does the shape of the bottle seem to affect it?
• Does the size and shape of the bottle seem to affect anything else, like the loudness of the sound or the tone quality?
• What do you think explains these effects?
• If using water in bottles, how does the amount of water affect the pitch/frequency? Why? (You may need to remind the students that it is the air in the bottle that is vibrating; more water means a smaller space for the air; smaller space means shorter waves and higher frequency/pitch).
• How is a bottle "instrument" the same as a wind instrument, and how is it different?
• If demonstrating with instruments: How does opening and closing the holes of the instruments change the pitch? Why? (Answer: the shorter the distance between the mouthpiece and the first open hole, the shorter the waves and the higher the pitch/frequency. Opening and closing other holes further down the instrument from the first open hole may have no discernible effect - they are not changing the length of the vibrating column of air - or if they are affecting the vibrating air a little, they may change the sound enough to make it more or less in tune.) If a brass instrument is used, what is the effect of opening a valve or extending the slide? (Opening valves actually lengthens the instrument, by opening up extra tubing, lowering the pitch.)

Percussion activity

Objectives and assessment

• Objectives - The student will assist in constructing a "found objects" chime, and will use the instrument to explore the effects of various object characteristics on frequency and amplitude.
• Evaluation - Assess student learning using worksheets or answers to discussion questions.

Materials and preparation

• Each working group will need a dowel, rod, or small beam, around 4-6 feet long, held at both ends about five feet off the ground.
• Each group will need a variety of objects of different sizes and materials. Forks, spoons, spatulas, rulers, wind chimes, lengths of chain, lengths of pipe or bamboo or tubing, are all easy to line up below the dowel because they are long and thin. Objects that have holes or handles (slotted spoons, pan lids) making it easier to keep them tied on, are also a good idea. Objects that are metal, hardwood, hard plastic, hollow, and/or made in a single piece are most likely to make easy-to-hear, interesting sounds.
• It may be easier to answer some of the discussion question if some of the objects are similar objects in a variety of sizes, for example small medium and large metal spoons.
• You will need enough string to hang the objects from the dowels, and may need tape to keep the objects on the string. Keep in mind, though, that tape will probably dampen the vibrations of the object so that it won't "ring" as long.
• You will need something the students can use to strike the objects; a wooden spoon, short stick, pen or pencil, or ruler. Or they can experiment with using different objects as "drumsticks". Which do the students prefer and why?
• For older or more independent students, you may want to make copies of the discussion questions.