All lessons › Solids, liquids and gases › Lesson 1
Australian primary science · Year 5 · Lesson 1 of 3
Zoom into water
Inquiry question: What are the particles doing in ice, water and water vapour?
Marked no materials needed
Using a model
What students learn
Everything is made of tiny particles, far too small to see. In a solid they are held in fixed positions and vibrate in place. In a liquid they are close but slide past each other. In a gas they are far apart and move fast in all directions.
Success criteria
- I can describe how particles are arranged in a solid, a liquid and a gas.
- I can describe how particles move in each state.
- I can use the model to explain what heating does.
Preparation and materials
Before this lesson: Students can name solids, liquids and gases and know that heating can melt ice.
- iPads with Bottlebrush Education open (nothing else needed) — 13 (one per pair)
- Projector or big screen — 1
Teacher setup
- Open Materials & chemistry › Lab › Heat it, cool it on your screen to demonstrate.
- Check the iPads are charged.
Safety and adaptations
Follow school science and equipment risk assessment procedures for the materials used.
Review your school policies and curriculum requirements before teaching.
How to investigate
The lesson sequence should leave pupils with evidence to interpret, not only an activity to finish.
- Pairs tap Ice, Liquid water and Water vapour in turn.
- For each state, record how the dots are arranged and how they move.
- Predict, then press Add heat and Remove heat and read the feedback.
- Link each state to what the substance does: keeps its shape, flows or spreads out.
Teacher modelling prompt
On the big screen tap Ice. Think aloud: “The dots are packed close in neat rows. Each one jiggles, but it stays in its place. That’s why ice keeps its shape.” Press Add heat and read the feedback: “Melting: adding enough heat changes ice into liquid water. It is still H₂O.” Ask: what changed about the dots?
Record and explain evidence
Recording question: What are the particles doing in ice, water and water vapour?
| State | How the particles are arranged | How the particles move | What the substance does (shape, flow, spread) |
|---|---|---|---|
| ________________ | ________________ | ________________ | ________________ |
Example recording headings; record actual observations, including inconclusive results.
Discussion prompt
What did the model show? Whose claim fits?
Check understanding
What should pupils know? Describe the particles in a solid.
Explain with evidence: Use the particle model to explain why liquid water can be poured but ice can’t.
Apply the idea: A drop of water on a hot footpath disappears. What happened to its particles?
Teacher answer guidance and saved classroom work are available through the main lesson experience where supported.