Activity 1
Use a pencil or a pen as a small lightweight striker.
Go around tapping things gently with the striker.
Try to find out which ones ring, or vibrate, and which ones simply make a dull thud.
Activity 2
Put a tambourine on a table. Sprinkle some table salt on to the surface of the tambourine. Now tap the tambourine with your striker. What do you SEE?