Ears and Hearing

Angelica Wright                Robert Fulton
6131 S. Campbell               5300 S. Hermitage
Chicago IL 60629               Chicago IL 60609
(312) 436-2149                 (312) 535-9000

Activity A
Objective:

To show sound waves

Materials Needed:

rubber band                                uncooked rice
plastic bowl                               scissors
sauce pan                                  large spoon
piece of medium plastic                    tape
  (like a throw-away plastic tablecloth)

Strategy:

1.  Cut the piece of plastic slightly larger than the bowl, allowing for the 
    rubber band to hold it.  
2.  Stretch the plastic over the bowl, using the rubber band to hold it in 
    place.
3.  Tape the edges of the plastic firmly to the bowl.
4.  Sprinkle a FEW grains of the rice on the stretched plastic.
5.  Hold the saucepan near the plastic.  Hit the bottom of the pan with the 
    spoon. 

Results:

As you hit the saucepan,the rice jumps up and down.  The vibrations of the pan 
give out the sound waves.  The sound waves travel through the air and make the 
plastic vibrate.  The vibrations can be clearly seen as the rice jumps up and 
down.

Activity B
Objective:

To follow written directions
To make a model that demonstrates how an ear works
To name by common and scientific names, the first three areas of the hearing 
   system

Materials Needed:

index cards                           plastic wrap
cardboard tube (from toilet tissue)   tape
flashlight                            sheet of paper
rubber band                           modeling clay


Procedure:

1.  Stretch the plastic wrap over one end of the tube.  Secure with a rubber 
    band.
2.  Roll the sheet of paper to make a cone.  Tape it together so that it does 
    not unroll.
3.  Push the small end of the cone into the open end of the cardboard tube.
4.  Put some modeling clay on the index card so that it stands vertically.  Lay 
    the tube in front of it.  Shine the flashlight on the plastic wrap so that a 
    spot of light is reflected onto the card. 
5.  Shout or sing loudly into the cone intermittently.  

Results:

The spot of light will shake very fast only when sound waves are captured.

The cone represents the outer ear (pinna); the tube represents the ear canal, 
and the plastic wrap, the eardrum (tympanic membrane).  As sounds waves are 
captured by the outer ear, and channeled down the ear canal, the tympanic 
membrane vibrates.

Performance Assessment:

Both of these activities can be PASS/FAIL per Teacher observation.

Students will name 2 or 3 of the following terms, and the corresponding 
structures on a diagram:   outer ear (pinna)
                           ear canal
                           ear drum (tympanic membrane)