Sound is made of waves.  A drum makes air vibrate.  Vibrate means to move back and forth.  This makes waves.  These are sound waves.  Our ears are able to hear the sounds!

The ocean and lakes have waves.  Waves are a movement back and forth.  Sound also makes waves.  The waves are in the air.

The ocean and lakes have waves.  Waves are a movement back and forth.  Sound also makes waves.  Sound waves are in the air.

Vibrate means to go back and forth. Sound waves vibrate.

Vibrate means to go back and forth. Sound waves vibrate.