You will learn
- Define evaporation.
- Observe drying.
- Test factors that speed evaporation.
- Explain drying clothes.
Version 0.2 · expanded edition · built from cited public sources Content is based on the official frameworks and sources listed under Sources and standards. No official endorsement is claimed. Written in the style of common primary school assessments. No exam result is promised.
Student lesson
- Liquids evaporate into gas.
- Warmth speeds evaporation.
- Wind speeds it too.
- Evaporation dries puddles and clothes.
Words to know
a liquid changing into a gas
water as an invisible gas
the size of the exposed surface
having no water left
1. Discover: The puddle and the sun
After rain, Kofi marks the edge of a puddle with chalk. By lunch the puddle is smaller and by evening it is gone. “Where did the water go?” he asks. “It evaporated into the air as water vapour,” says his teacher.
Think: What made it go faster in the Sun?
2. Understand: Evaporation
Idea 1: What is evaporation?
Evaporation is when a liquid changes into a gas. Water turns into invisible water vapour and mixes with the air.
Idea 2: Speeding it up
Evaporation is faster when it is warm, windy and when the water has a large surface area, like a wide saucer.
Idea 3: Everyday
Wet clothes dry on a line, puddles disappear, and sweat cools us because of evaporation.
3. Worked examples
Example 1 (I show you): Define
Puddle gone.
- Liquid to gas.
- Vapour.
- Evaporation.
Answer: The puddle evaporated.
Example 2 (We do it together): Speed
Sunny day.
- Warm.
- Faster.
- Evaporation.
Answer: Warmth speeds evaporation.
Example 3 (You try): Area
Wide saucer.
Show the steps and answer
- Large surface.
- Faster.
- Evaporation.
Answer: Wide surface speeds evaporation.
Did you know?
The Sun’s energy evaporates about 500,000 cubic kilometres of water from Earth’s oceans and land every year.
Why this matters
Evaporation drives the water cycle and dries our clothes and crops.
4. Explore: Evaporation race
Compare drying in different places.
- Put equal water on three saucers.
- Place one in Sun, one in shade, one indoors.
- Check every hour.
- Record when each dries.
Think about it: what did you notice?
What did you notice? The saucer in the Sun dried first.
5. Practise
Say it in a sentence
Use these starters when you talk about the lesson. Say them out loud.
- Evaporation turns liquid into ___.
- Water vapour is ___.
- ___ speeds it up.
- Wet clothes ___ outside.
Guided practice
Question 1. What is evaporation?
Liquid to gas.
Question 2. What is water vapour?
Invisible gas.
Question 3. What speeds it up?
Warmth.
Independent practice
Level 1: Start
- What is evaporation?
- What is water vapour?
- What speeds it up?
- What else?
- Name a daily example.
Level 2: Grow
- Why dry in Sun?
- Why wide saucer?
- Why does wind help?
Level 3: Stretch
- Do the race.
- Draw evaporation.
- Explain drying clothes.
Answers are in the answer key below. Try first, then check.
6. Apply: Science in everyday life
Where have you seen evaporation?
Show a sample answer
Puddles.
Another one. Tell a family member one thing from this lesson. Use the words you learned.
Show a sample answer
A clear sentence that uses at least one word from Words to know.
7. Common mistakes
Fix: It becomes vapour.
Fix: It happens at any temperature.
8. Lesson summary and revision card
- I can define evaporation.
- I can observe drying.
- I can test factors that speed evaporation.
- I can explain drying clothes.
9. Check and master
Answer all 14 questions. You will see feedback after each one.
Your result appears here after you answer every question.
10. Key takeaways
- Liquids evaporate into gas.
- Warmth speeds evaporation.
- Wind speeds it too.
- Evaporation dries puddles and clothes.
11. Next lesson
Next lesson: Material selection. Keep going with the next idea in this course.
Exam practice
These questions are written in the style of common school and international primary assessments. Try them on your own, without looking back. Then check your answers in the marking guide. The marks are shown in brackets.
- Define evaporation. [2 marks]
- Name two things that speed it up. [2 marks]
- Describe the saucer race. [3 marks]
- Give an everyday example. [1 mark]
- Safety rule? [2 marks]
Total: 10 marks.
Marking guide and model answers
- Liquid [1]; to gas [1]
- Warmth [1]; wind/surface [1]
- Equal water [1]; different places [1]; record [1]
- Any [1]
- No boiling water [1]; never look at Sun [1]
Score guide: 9 to 10 = secure. 6 to 8 = nearly there, revise the parts you missed. Under 6 = work through the lesson again with a grown-up.
Printable worksheet
- What is evaporation?
- What is water vapour?
- What speeds it up?
- What else?
- Name a daily example.
- Why dry in Sun?
- Why wide saucer?
- Why does wind help?
- Do the race.
- Draw evaporation.
Homework
Put equal water on two saucers, one inside, one outside, and record when each dries.
Answer key and marking scheme
| Question | Expected response | Marks |
|---|---|---|
| 1. What is evaporation? | Liquid to gas. | 1 |
| 2. What is water vapour? | Invisible gas. | 1 |
| 3. What speeds it up? | Warmth. | 1 |
| 4. What else? | Wind. | 1 |
| 5. Name a daily example. | Drying clothes. | 1 |
| 6. Why dry in Sun? | Warm. | 1 |
| 7. Why wide saucer? | More surface. | 1 |
| 8. Why does wind help? | Carries vapour. | 1 |
| 9. Do the race. | Table. | 1 |
| 10. Draw evaporation. | Diagram. | 1 |
| Total | 10 |
Independent practice answers. Level 1: 1 Liquid to gas.; 2 Invisible gas.; 3 Warmth.; 4 Wind.; 5 Drying clothes.. Level 2: 1 Warm.; 2 More surface.; 3 Carries vapour.. Level 3: 1 Table.; 2 Diagram.; 3 Paragraph..
Quiz answers: 1 B, 2 C, 3 A, 4 B, 5 C, 6 A, 7 B, 8 C, 9 A, 10 B, 11 C, 12 A, Challenge 1 B, Challenge 2 C.
Mastery and remediation
| Objective | Bronze (Developing) | Silver (Proficient) | Gold (Advanced) |
|---|---|---|---|
| O1 Define evaporation | Shows this with help from an adult or a picture | Does this independently and explains how they know | Explains it clearly and uses it in a new situation |
| O2 Observe drying | Shows this with help from an adult or a picture | Does this independently and explains how they know | Explains it clearly and uses it in a new situation |
| O3 Test factors that speed evaporation | Shows this with help from an adult or a picture | Does this independently and explains how they know | Explains it clearly and uses it in a new situation |
| O4 Explain drying clothes | Shows this with help from an adult or a picture | Does this independently and explains how they know | Explains it clearly and uses it in a new situation |
Courseversity badge thresholds (overall quiz score): Gold = 90–100%; Silver = 80–89.9%; Bronze = 70–79.9%. A badge is never a full record of progress.
If a learner struggles
- Find the misconception: “Water disappears.” It becomes vapour.
- Explain another way: use real objects, pictures or actions first, then words.
- Show a simpler example: Explain evaporation and what speeds it up.
- Guided practice: work through one example together and let the learner try the next one.
- Reassess: use the quiz again or the worksheet.
- Move on when the learner shows Silver-level evidence independently.
For parents and guardians
In this lesson your child studies evaporation. You do not need to be an expert to help.
- Hang a wet cloth outside.
- Ask, “Why did it dry?”
- Never look at the Sun.
- Ask “how do you know?” after each answer, and listen.
- Praise effort, not only right answers. Mistakes are how we learn.
- Ten to fifteen minutes a day is better than one long session.
Teacher package
1–5. Objectives, prerequisites, materials, preparation, duration
Lesson objectives. Learners will: define evaporation; observe drying; test factors that speed evaporation; explain drying clothes.
Prerequisite knowledge. Grade 2 matter ideas: solids and liquids, air and water, and the properties of everyday materials.
Materials. Saucers, water, chalk, timers. Low-resource options: use chalk or charcoal on a board or wall, drawings in the sand, and objects from the classroom instead of printed materials.
Preparation. Choose Sun and shade spots.
Suggested duration. 45–60 minutes. It can be split into two shorter sessions.
6–9. Teaching procedure, explanation notes, guided and independent activities
Introduction (5 min). Show a wet cloth and ask, “Where does the water go?”
Explanation (10 min). Teach evaporation.
Guided activity (10 min). Learners test.
Independent activity (10 min). Learners compare.
Assessment and reflection (5 min). Ask each learner to say one thing they learned and how they know it.
Key questions. Where did the water go? What sped it up?
Teacher explanation notes. Start with real objects and safe, hands-on observation. Then talk about what was seen, then draw and write. Always say “how do you know?”. Keep to the safety notes, and use local, safe materials.
10–12. Differentiation, formative assessment, common misconceptions
Support. Use real objects and pictures, short sentences and a partner. Let learners point, show or draw instead of writing. Extension. Ask learners to find a new example at home and explain how they know.
Formative assessment. Listen to learners read and explain, ask “how do you know?”, and check the independent work.
Misconceptions. “Water disappears.” It becomes vapour.
13–15. Assessment questions, answer keys, marking scheme
Use the quiz, the 10-mark exam practice and the worksheet on this page. All answers and marking guides are in the answer sections above. Re-check every answer before use.
16–19. Remediation, enrichment, homework, teacher reflection
Remediation. Explain evaporation and what speeds it up. Enrichment. Look for one new example near your home or school, draw it and explain it to someone. Homework. See above.
Teacher reflection. After teaching, record: which ideas learners understood; which misconceptions occurred; which activities worked; which learners need more practice; and what to improve next time.
Sources and standards
This lesson is based on the sources below, and no official endorsement is claimed. Reference starting points: Next Generation Science Standards, Cambridge Primary Science and the IB Primary Years Programme. Where a standard code is named, it points to the official framework.
Research used to shape this lesson. Courseversity Science curriculum, Grade 3 Unit 5, topic 9; Next Generation Science Standards, structure and properties of matter; Cambridge Primary Science Stage 3, materials; IB Primary Years Programme, how the world works. These sources informed the lesson.