Sound 

Anne Chamberlain               Bethune Elementary
                               3030 W Arthington Avenue
                               Chicago IL 60612
                               (312) 532-6890                      

Objective 1:

Children shall "discover" that sound waves can be directed with a 
megaphone and collected with an ear trumpet.

Materials Needed:

Each group of four or five students will need a megaphone/ear trumpet 
(roll and staple poster paper into a conical shape) and a ticking device
(clock or timer).

Strategy:

1.  Participants speak to one another--first normally, then with hands
    cupped around their mouths, and finally through a megaphone.  They  
    talk about any differences they notice.

2.  Participants listen to one another--first normally, then with hands
    cupped behind their ears, and finally through an ear trumpet.  They
    talk about differences they notice.

3.  Each member of the group counts how many paces away he can hear a
    ticking device--first with the unaided ear, then with an ear
    trumpet.  The group will compare the distances, and draw a 
    conclusion.
  
Conclusion:

Sound waves can be collected and directed into our ear and increase
our ability to hear.

Objective 2:

Children shall "discover" that sound travels differently through a solid,
a liquid, and a gas. 

Materials needed:

Each child or group will need a 40 cm piece of 5 cm flexible tubing:
an aluminum foil pan: 60 cm of string: tape: a stethoscope: a can of soda:
a drinking glass: and a 3 liter tub of water.

Strategy:
 
After each of the following activities the students name the material the
sound traveled through (a solid, a liquid or a gas).  They record through
which state of matter they heard better.

1.   Hold one end of a piece of tubing to your mouth and the other end 
     in your ear as you talk.

2.   Tape a foil pan to the middle of a piece of sting.  Bang the pan 
     against your desk and listen.  Twist the ends of the string around
     the tips of your index fingers.  Place those finger in your ears.
     Bang the pan and listen again.

3.   Listen as you knock on your desk.  Place a stethoscope (or your ear)
     against the desk as you knock again.

4.   Open a can of soda.  Listen to the bubbles.  Place the can next to
     your ear and listen again.

5.   Listen to the classroom next door.  Place the open end of a drinking
     glass against the wall and your ear against the bottom of the glass
     and listen again.

6.   Volunteer students listen to tapping sounds made against a tub of
     water.  Then place one ear into the water while holding the other
     ear shut and listen again.

Conclusion:

Sound is transmitted best through solids, next though liquids, then through
gases.