Are your students curious about why their stringed instruments sound the way they do? An easy way to explain might be to use a piece of equipment typically found in gym class.
A jump rope shares certain properties with a string on a violin, viola, cello or bass—namely, flexibility and great length in relation to thickness. Get two volunteers from your class and have each hold an end of the rope. Ask one student to shake the rope hard while the other student holds the opposite end still. Next, have them see how softly they can shake it.
In scientific terms, this will show amplitude, but in written music, volume is represented by dynamics symbols. The more pressure a string player puts on the bow, the higher the volume (or amplitude) will be. See if jump-rope-holding students can maintain a steady pattern using the full range of soft to hard movements.
Two more volunteers can help you demonstrate frequency, known more commonly in musical terms as pitch. Ask these students to each hold one end of the rope, then have the active-end student shake the string. Now, present a challenge to your volunteers: If they leave a bit of slack behind the active end, can they find a way to make the string shake in a regular pattern? See how small an amount of rope they’re able to have between them while still making wave shapes in the jump rope.
The wave shapes should become narrower and narrower as a smaller section of rope is used. This is the equivalent of a string player’s fingers moving higher up on a string, and in written music, such directions are conveyed by how high on the staff a note is.
For an extra challenge, visit Advanced Jump Rope in Orchestra Class for the jump-rope version of stringed instrument harmonics.
—Gregory Reinfeld, January 19, 2012. © National Association for Music Education