This unit is one of my all-time favorites. In fact, it's the only unit I've taught all 19 years of my career.
Lesson 1: Put a bunch of world instrument pictures on the board. Students must figure out how to categorize them into 4 groups, based on the question "what vibrates to make the sound?" With a little direction from me, they end up with these:
strings (chordophones)
solid material (idiophones)
stretched skin (membranophones)
air (aerophones)
Lesson 2: I explain the Invented Instrument assignment and show pictures.
Lessons 3,4: Students browse books for ideas, fill out the plan form, and bring in materials to build if they want to (most would rather work at home).
Lessons 5-6: Explain sound piece, work in class
