Hidden depths

Activity overview

Run the activity

You will be zooming in and out of the image above – starting very close and stepping back slowly.

1. Start by asking everyone:

• What do they think the image is and why?
• What does the image remind them of and why?

2. Every time you zoom out, ask the class:

• Can they describe the colours, shapes and textures?
• What do they think the image is now – have they changed their minds?

Background science

All sounds are created by vibrations. A vibration is when an object moves backwards and forwards very quickly. Invisible sound waves travel through the air to our ears. Our outer ear, the bit we can see, funnels the sound waves into the parts of the ear inside our heads. Ear wax is produced here to trap dirt and to help prevent infections. The sound waves cause our ear drum, which is a piece of sensitive, tightly stretched skin, to vibrate. These vibrations are then transmitted to tiny bones and fluid in our inner ear. The movement of this fluid stimulates nerve endings which carry messages to our brains that are interpreted as sound. 

The human outer ear is not as large as in many other animals. Unlike other animals, our ears do not move independently. This means that we are not as good at hearing sound as many animals and when we are trying to locate the direction of a sound, we need to turn our whole heads to help our ears to ‘catch’ the sound waves. 

Watch out for:   

When sound travels through the air into our ears, children may think that the air particles move from the sound source to the ear. But this is not the case. It is the vibration that is passed from one air particle to the next, until it reaches the ear drum. Find further details in our Sound Tackle the Tricky bits and from the Primary Science Teaching Trust with the download here. This does not need to be corrected during the session; you can pick it up later. 

Take it further

Activities  

Children could research how the human ear works. This TIME for Kids resource is a good starting point and has a read aloud function. Small groups of children could make a model ear drum using the guidance here and observe how it reacts to loud sounds. The site also suggests a game to explore how out two ears work together to locate sounds. 

Watch 

Children could watch this BBC video which will help them understand how the human ear works.  

Linked Explorify activities- our recommendations: 

Compare the human ear with that of a cat with Pink and knobbly. Watch the vibrations in Rice and rhythm and Good vibrations.