All lessons › Material matters › Lesson 4
Australian primary science · Years 3–4 · Lesson 4 of 6
Keep it warm
Inquiry question: How can wrapping a hot drink keep it warm for longer?
Check practical materials
Pattern seeking
What students learn
Some materials slow heat moving through them better than others (insulators), which influences their use.
Success criteria
- I can read temperatures from a table or graph.
- I can describe a pattern in the results.
- I can explain which material is the best insulator using the data.
Preparation and materials
Before this lesson: Students can plan a fair comparison (lesson 3).
- Identical cups — 5 per group of 4 (35)
- Wraps: wool sock, aluminium foil, bubble wrap, paper towel, none — 1 set per group
- Thermometers (if available) — 5 per group
- Warm tap water, about 50°C, prepared by the teacher — 1 jug per group
- Rubber bands — 1 bag
Teacher setup
- If you have thermometers, practise reading one.
- If not, print the supplied data table or use the Keep it warm simulation.
Safety and adaptations
- The teacher pours the water. Tap water no hotter than 50°C.
- Glass (alcohol-filled) thermometers can break: use digital thermometers if possible, handle glass ones carefully, and never use mercury thermometers. Otherwise use the supplied data.
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.
- Predict which wrap will keep water warmest.
- If you have thermometers: wrap the cups, pour in warm water, record the temperature at 0, 10 and 20 minutes.
- If not: use the illustrative data table or the Keep it warm model. Label the evidence as supplied data or model results, not your own measurements.
- Describe the pattern: which wraps kept the water warmest?
- Explain why using the word insulator.
Teacher modelling prompt
Display the supplied table. Read one row aloud: “The cup with no wrap started at 50°C and was 35°C after 20 minutes.” Then compare: “The wool cup was 42°C. So the wool cup lost less heat.” Show how to find the pattern by comparing the final temperatures for all cups.
Record and explain evidence
Recording question: Which wrap keeps water warmest?
| Wrap | Start (°C) | After 10 min (°C) | After 20 min (°C) |
|---|---|---|---|
| ________________ | ________________ | ________________ | ________________ |
Example recording headings; record actual observations, including inconclusive results.
Discussion prompt
How could you test which claim is right? (Hint: think about an ice block.)
Provided example or reference data
Illustrative cooling data (written for this lesson; not measured classroom results)
| Wrap | Start | 10 min | 20 min |
|---|---|---|---|
| No wrap | 50°C | 41°C | 35°C |
| Foil | 50°C | 43°C | 37°C |
| Paper towel | 50°C | 43°C | 38°C |
| Bubble wrap | 50°C | 45°C | 41°C |
| Wool sock | 50°C | 46°C | 42°C |
Check the data source in the teacher lesson. Illustrative or fictional data are not measurements collected by your class.
Check understanding
What should pupils know? What is an insulator? Name the best insulator from today’s results.
Explain with evidence: After 20 minutes the cups were: no wrap 35°C, foil 37°C, wool 42°C. Describe the pattern.
Apply the idea: Why do saucepan handles often have a plastic or wooden cover?
Teacher answer guidance and saved classroom work are available through the main lesson experience where supported.