Science · Year 2 · The Science of Sound · Term 3

How We Hear

Students will learn the basic parts of the ear and how they work to detect sound vibrations.

• ACARA Content Descriptions
• AC9S1U03

About This Topic

Sound is one of our most important tools for communication. In this topic, students explore how humans and animals use sound to share information, express emotions, and stay safe. They look at everything from bird calls and whale songs to sirens and spoken language. This connects to the 'Science as a Human Endeavour' strand by showing how we use sound technology in our communities.

In Australia, sound has always been a way to connect with Country. Students will learn about the use of 'clapsticks' (Bilma) in storytelling and how different bird sounds can signal changes in the weather or the presence of water. Students grasp this concept faster through structured discussion and peer explanation, where they can decode 'secret' sound signals and design their own communication systems.

Key Questions

1. Explain how our ears help us hear sounds.
2. Compare how a drum vibrates to how our eardrum vibrates.
3. Analyze the importance of our ears for understanding the world.

Learning Objectives

• Identify the main parts of the human ear involved in hearing.
• Explain how sound vibrations travel through the ear to the brain.
• Compare the vibration of a drum surface to the vibration of the eardrum.
• Analyze how hearing contributes to understanding the environment and communicating with others.

Before You Start

Properties of Materials

Why: Students need to understand that different materials can be made to vibrate to grasp how sound is produced.

Push and Pull

Why: Understanding basic forces helps students conceptualize how sound waves push and pull on the eardrum.

Key Vocabulary

Eardrum	A thin membrane inside the ear that vibrates when sound waves hit it.
Vibration	A rapid back-and-forth movement that produces sound.
Sound waves	Invisible ripples of energy that travel through the air and cause objects to vibrate.
Ear canal	The tube that connects the outer ear to the eardrum.

Watch Out for These Misconceptions

Common Misconception

Students might think that we only communicate with words.

What to Teach Instead

Play a game of 'Sound Charades' where students have to communicate an emotion (happy, scared, angry) using only 'nonsense' sounds. This helps them see that pitch and volume carry meaning too.

Common Misconception

Children may believe that animals only make noise for no reason.

What to Teach Instead

Watch clips of animal behaviour (like a mother bird calling her chicks). Discussing the 'purpose' of the sound helps students understand that in nature, sound is a survival tool.

Active Learning Ideas

Role Play: Animal Signals

Assign students an animal (e.g., a kookaburra or a whale). They must use a specific sound to 'call' their group together or 'warn' them of a predator, discussing why sound is better than sight in a thick forest or deep ocean.

30 min·Small Groups

Gallery Walk: Community Sounds

Students draw or find pictures of things that use sound to tell us something (a school bell, a smoke alarm, a 'walk' signal at a crossing). They display these and peers must guess what 'message' each sound is sending.

40 min·Individual

Inquiry Circle: The String Telephone

Groups build classic tin-can-and-string telephones. They experiment with keeping the string tight versus loose and discuss how the sound 'travels' as a vibration along the string to communicate over a distance.

45 min·Pairs

Real-World Connections

• Audiologists, like those at the Royal Victorian Eye and Ear Hospital, test people's hearing and fit hearing aids to help them hear better.
• Musicians use instruments like drums, which produce sound through vibration, to create music. They must understand how vibrations create different sounds.

Assessment Ideas

Quick Check

Show students a diagram of the ear. Ask them to point to and name the eardrum and ear canal. Then, ask: 'What happens to the eardrum when sound waves enter the ear?'

Exit Ticket

On a small piece of paper, have students draw a simple picture showing how sound travels to the ear. Ask them to label at least two parts of the ear and write one sentence explaining what happens when sound enters the ear.

Discussion Prompt

Ask students: 'Imagine you are in a noisy playground. How do your ears help you hear your friend calling your name? What might happen if your eardrum could not vibrate?'

Frequently Asked Questions

How do Aboriginal people use sound for communication?

Beyond language, sound is used through instruments like Bilma (clapsticks) to keep the rhythm of stories and songs that hold important information about the land. Some groups also used 'message sticks' accompanied by specific verbal messages delivered by runners.

What are some 'warning sounds' in our school?

The fire alarm, the school bell, and even a teacher's whistle. These are all designed to be loud and have a specific pitch that grabs our attention immediately, which is a great link to the science of sound.

How can active learning help students understand communication?

By trying to communicate *without* their usual tools (like in the 'Animal Signals' role play), students realise how efficient sound is. Active learning forces them to think about the 'sender' and the 'receiver', which is the basis of all communication science.

Why do some animals use sound instead of colours to talk?

This is a great 'Think-Pair-Share' topic! Sound can go around corners, through trees, and works in the dark. For animals that live in the bush or the ocean, sound is often the most reliable way to be 'seen'.