Arrange a series of three glasses on a flat surface. Use glasses of the same size and shape and place them in a row.
Fill the first glass with only an inch or two of water.
Fill each successive glass with a little more water than the glass before it.
Tap each glass with a spoon to hear the pitches produced. The less water in a glass, the lower the pitch, and the more water in a glass, the higher the pitch will be.
Experiment with adding and pouring out small amounts of water until you can create three successive notes of the scale. If you successfully do this, you should be able to play a simple song such as "Hot Cross Buns." If you label the most empty glass "low," the glass with the medium level of water "med," and the fullest glass, "hi," you can play the song as follows:
HI--MED--LOW
HI--MED--LOW
LOW-LOW-LOW-LOW
MED-MED-MED-MED
HI-MED-LOW