10. Bat Beeps (lesson plan provided)

• Health/Science
  
• discuss principles of sound and hearing in humans, then relate it to sounds bats make and how this is used for echolocation
  
• simulate echolocation in a gym by blindfolding some students to represent bats and letting the other students represent obstacles and food. The bats must make beeps and travel from their "cave" in search of food, and then return. Obstacles make one kind of noise and remain stationary, while the "food" makes a different noise and moves around slowly. The bats must find the food and avoid the obstacles by using their ears

Bat Beeps

CELs:

• explore and express the purpose for and the meaning of what they are doing (C)
  
• understand the benefits and limitations of technological tools used within subject areas (TL)
  
• strengthen their perceptual abilities through concrete experiences or situations (CCT)

Materials:

• model or drawing of the human ear
  
• overhead illustrating sound wavelengths
  
• overhead illustrating echolocation (see Discovering Bats or America's Neighbourhood Bats)

Objectives:
Students will learn that:

• we hear by sensing sound waves in the air
  
• bats can fly in the dark by using echolocation

Procedure:
Set Induction (10 min.)

• ask students for ideas of why bats can fly in the dark without crashing into things - make concept web
  
• if not suggested explain that bats have a form of built in radar
• Main Procedure (2 hours)
  
• explain how our ears sense sound waves in the air (show model)
  
• explain how our ears can only sense certain levels of sound whereas bats can sense much higher frequencies (show overhead)
  
• explain that bats produce high frequency sounds and then listen for the reflection of these sounds to judge where obstacles or prey is (show overhead)
  
• go to the gym (or other large empty space) and simulate the echolocation of bats by setting up the following groups:
  1. bats - blindfold students and place them in a corner which represents their roost - they repeat the word "bat" when they move
     
  2. wall guards - watch so bats don't hit the walls - they repeat the word "wall"
     
  3. obstacles - are stationery and repeat the word that describes themselves e.g. "tree"
     
  4. prey - move around slowly and repeat the word that describes themselves e.g. "moth"
• The bats must go out from their roost and by listening to the clues they hear, capture a prey and return to the roost without hitting anything. One bat should stay in roost (saying "roost") to help the other bats find their way back.

Closure (15 min.)

• review echolocation by listening to what the bats experienced

Evaluation:

• ask students to list how our hearing is similar to bat hearing and how it is different from bat hearing
  
• retest the class with the Bat-O-Meter to test for changes in empathy levels (see unit evaluation)