Energy and Its Forms

Making Your Own Harmonica

ENERGY and its forms

Duration: 90 minutes

Notes / Activity

Using DIY materials:

1. Design and build a harmonica

  • 1-PS4-1. Plan and conduct investigations (Tuning fork to provide evidence that vibrating materials can make sound and that sound can make materials vibrate).

By the end of this lesson, the student should able to:

  • Develop models to explain the concept of vibrating materials making sound.

Lesson Plan

Lesson Introduction

Duration: 10 min

Prepare these materials before lesson:

  • 4 empty glass bottles of the same size
  • jar of water
  • pencil
  • 4 empty glass bottles of the same size
  • jar of water
  • pencil

Pitch demonstration:

 

  • Arrange the glass bottles in a row and have one volunteer to fill the first bottle to the brim with water. 
  • Have the student blow across the top of the bottle and observe the sound (pitch) coming from the bottle. 
  • Have another volunteer to fill the second bottle with a little less water than the first and blow them.
  • Have two more volunteers to fill up the third and fourth bottles and blow across them.
  • Ensure that students do not put their mouths directly on the bottles and get them to be careful when they use the pencil to tap on the glass bottles. 
  • Elicit from students:

 

What difference can you hear in the pitch of the bottles? 

 

  • Have students tap on the first bottle with a pencil. Observe the sound (pitch).
  • Tap the remaining glasses and observe the sound (pitch) as well. 

Explain

Duration: 15 min

  • Ask students which glass produced the highest pitch (Bottle with more water).

 

Why does the bottle with more water produce the highest pitch?”

 

  • Explain to students that different sounds are produced by changing the length of the object or air volume through which the air vibrates.
  • Shorter air columns produce higher pitches than longer air columns. 

Elaborate – Individual Activity

Duration: 45 min

Prepare these materials before lesson:

 

  • Large craft sticks (at least six inches long)
  • Rubber bands
  • Plastic drinking straws
  • Ruler
  • Scissors
  • Papers
  • Pen or pencil
  • Large craft sticks (at least six inches long)
  • Rubber bands
  • Plastic drinking straws
  • Ruler
  • Scissors
  • Papers
  • Pen or pencil
  • Present a problem to the students. 

 

You have been challenged to create a harmonica to produce high pitch and low pitch sounds using the materials provided. How are you going to do that?

 

  • Challenge students to design their own harmonica and apply the concepts that they have learned about sound and pitch. Have them research and brainstorm ideas to create the harmonica using the materials provided by the teacher. Guide students on how they can create their harmonica if they are unsure. 
  • After creating their instrument, they will test their harmonicas to see if they can produce a sound.  
  • Have students investigate how the position of the straws affects the pitch of the sound produced. If their harmonica is not working, have them improve it by changing materials. 
  • Let students share their answers.  
  • Elicit from students:

 

What sound do you hear?

Do you feel anything in your hands as you blow through your instrument?

Can you change the tone of the sound by moving the straw?

 

Evaluate – Pair Activity

Duration: 30 min

  • Instruct students to produce different sounds on their harmonica, such as short and high notes, long and low notes. 
  • In pairs, students will design, test and see if they can play the tune together.
  • Students will perform their patterns to the class.