All lessons › Surviving Australia’s extremes › Lesson 3
Australian primary science · Year 5 · Lesson 3 of 3
Leaf water savers
Inquiry question: Which leaf shape or covering keeps water in the longest?
Check practical materials
Fair testing
What students learn
Plants lose water from their leaves. Structural features such as rolled leaves and waxy coatings reduce water loss, helping plants survive in dry habitats.
Success criteria
- I can plan a fair test with one changed variable.
- I can record observations at regular times.
- I can link my results to plant features that save water.
Preparation and materials
Before this lesson: Students know desert plants have features such as rolled or waxy leaves (lesson 1).
- Paper towel (cut each sheet in half; all pieces the same size) — 52 half-sheets (4 per pair)
- Cling wrap, cut into half-sheet sizes — 26 pieces (2 per pair)
- Paper clips or sticky tape — 1 small box or roll
- Teaspoons — 13
- Cups of water — 13
- Trays or large plates — 13
- Timer (iPad or class clock) — 1 per pair or the class clock
- Kitchen scales (optional, if the school has them) — 1–2
Teacher setup
- Find a sunny windowsill or a warm spot outside in the sun; set the leaves out early in the lesson so they have time to dry.
- Cut paper towel and cling wrap to size.
- Print one investigation record per pair.
Safety and adaptations
- Wipe up spills straight away so no one slips.
- Wear hats if working outside.
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 write their fair test plan: what they will change, observe and keep the same.
- Wet four half-sheets of paper towel with exactly 2 teaspoons of water each.
- Make them into model leaves: A flat (no cover), B flat with cling wrap on top (waxy coating), C rolled up tightly and held with a paper clip (rolled leaf), D flat with cling wrap on both sides.
- Put them side by side on a tray in the sun.
- Every 10 minutes, gently touch each leaf (or weigh it) and record wet, damp or dry.
- Rank the leaves from driest to wettest at the end.
Teacher modelling prompt
Show a flat damp “leaf” and one covered with cling wrap. Think aloud: “The thing I change is the leaf’s feature. I keep the paper size, the amount of water and the place the same. Every 10 minutes I’ll touch each one gently and record wet, damp or dry.” Model filling in the plan.
Record and explain evidence
Recording question: Which leaf shape or covering keeps water in the longest?
| Model leaf | Real feature it models | After 10 minutes | After 20 minutes | After 30 minutes |
|---|---|---|---|---|
| ________________ | ________________ | ________________ | ________________ | ________________ |
Example recording headings; record actual observations, including inconclusive results.
Discussion prompt
Which claim takes into account what a real leaf needs?
Check understanding
What should pupils know? How does a waxy coating help a plant survive in a dry habitat?
Explain with evidence: Leaf C (rolled) was still damp inside when leaf A (flat) was dry. Explain why, using the words surface and evaporate.
Apply the idea: A gardener in a hot, dry town wants plants that need little watering. What leaf features should she look for? Why?
Teacher answer guidance and saved classroom work are available through the main lesson experience where supported.