You will learn
- Define melting and freezing.
- Observe ice melting.
- Explain freezing.
- Link changes to temperature.
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
- Heating can melt a solid.
- Cooling can freeze a liquid.
- Water freezes at 0°C.
- Melting and freezing are reversible.
Words to know
changing from solid to liquid
changing from liquid to solid
the temperature at which a solid melts
able to change back
1. Discover: The ice lolly
On a warm day Yaa holds an ice lolly. It begins to drip. “The solid ice is melting,” her father says. “If we put the drips back in the freezer, they will freeze again.”
Think: Why does warmth make ice melt?
2. Understand: Melting and freezing
Idea 1: Melting
Melting is when a solid becomes a liquid as it warms. Ice melts into water; chocolate melts in warm hands.
Idea 2: Freezing
Freezing is when a liquid becomes a solid as it cools. Water freezes at 0 °C. Candle wax and chocolate also freeze (set) when they cool.
Idea 3: Reversible
Melting and freezing are reversible: warm the ice to melt it, then cool the water to freeze it again. Different materials have different melting points.
3. Worked examples
Example 1 (I show you): Melt
Ice at room.
- Warms.
- Becomes water.
- Melts.
Answer: Ice melts in warmth.
Example 2 (We do it together): Freeze
Water in freezer.
- Cools.
- Becomes ice.
- Freezes.
Answer: Water freezes when cold.
Example 3 (You try): Reverse
Melt then freeze.
Show the steps and answer
- Water to ice.
- Ice to water.
- Reversible.
Answer: Melting and freezing are reversible.
Did you know?
Lava is rock that has melted so hot that it flows, then freezes into solid rock as it cools.
Why this matters
Melting and freezing explain ice, ice-cream and how metals are shaped.
4. Explore: Ice melt race
Compare how fast ice melts in different places.
- Place equal ice cubes in a cup in shade, sunlight and warm hands.
- Time until each melts.
- Record.
- Compare.
Think about it: what did you notice?
What did you notice? Ice melted faster where it was warmer.
5. Practise
Say it in a sentence
Use these starters when you talk about the lesson. Say them out loud.
- Melting turns a solid to a ___.
- Freezing turns a liquid to a ___.
- Water freezes at ___ °C.
- These changes are ___.
Guided practice
Question 1. What is melting?
Solid to liquid.
Question 2. What is freezing?
Liquid to solid.
Question 3. At what temperature does water freeze?
0 °C.
Independent practice
Level 1: Start
- What is melting?
- What is freezing?
- At what temperature does water freeze?
- Are they reversible?
- Name a solid that melts.
Level 2: Grow
- Why does ice melt faster in the Sun?
- Why does chocolate set in a fridge?
- Why reversible?
Level 3: Stretch
- Do the ice race.
- Draw melting and freezing.
- Explain reversible.
Answers are in the answer key below. Try first, then check.
6. Apply: Science in everyday life
Name a material that melts.
Show a sample answer
Chocolate.
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: Same material.
Fix: Many solids melt.
8. Lesson summary and revision card
- I can define melting and freezing.
- I can observe ice melting.
- I can explain freezing.
- I can link changes to temperature.
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
- Heating can melt a solid.
- Cooling can freeze a liquid.
- Water freezes at 0°C.
- Melting and freezing are reversible.
11. Next lesson
Next lesson: Evaporation. 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 melting and freezing. [2 marks]
- Describe the ice race. [3 marks]
- Why are they reversible? [2 marks]
- Water freezes at what temperature? [1 mark]
- Safety rule? [2 marks]
Total: 10 marks.
Marking guide and model answers
- Melting [1]; freezing [1]
- Equal ice [1]; time [1]; record [1]
- Change back [1]; same material [1]
- 0 °C [1]
- No flames [1]; adult [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 melting?
- What is freezing?
- At what temperature does water freeze?
- Are they reversible?
- Name a solid that melts.
- Why does ice melt faster in the Sun?
- Why does chocolate set in a fridge?
- Why reversible?
- Do the ice race.
- Draw melting and freezing.
Homework
Freeze water in a tray with an adult and see how long it takes to melt.
Answer key and marking scheme
| Question | Expected response | Marks |
|---|---|---|
| 1. What is melting? | Solid to liquid. | 1 |
| 2. What is freezing? | Liquid to solid. | 1 |
| 3. At what temperature does water freeze? | 0 °C. | 1 |
| 4. Are they reversible? | Yes. | 1 |
| 5. Name a solid that melts. | Ice. | 1 |
| 6. Why does ice melt faster in the Sun? | Warmer. | 1 |
| 7. Why does chocolate set in a fridge? | Cools. | 1 |
| 8. Why reversible? | Change back. | 1 |
| 9. Do the ice race. | Table. | 1 |
| 10. Draw melting and freezing. | Diagram. | 1 |
| Total | 10 |
Independent practice answers. Level 1: 1 Solid to liquid.; 2 Liquid to solid.; 3 0 °C.; 4 Yes.; 5 Ice.. Level 2: 1 Warmer.; 2 Cools.; 3 Change back.. 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 melting and freezing | 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 ice melting | 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 Explain freezing | 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 Link changes to temperature | 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: “Melting makes new material.” Same material.
- Explain another way: use real objects, pictures or actions first, then words.
- Show a simpler example: Explain melting and freezing.
- 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 melting and freezing. You do not need to be an expert to help.
- Watch ice melt together.
- Ask, “Can it change back?”
- Keep away from flames.
- 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 melting and freezing; observe ice melting; explain freezing; link changes to temperature.
Prerequisite knowledge. Grade 2 matter ideas: solids and liquids, air and water, and the properties of everyday materials.
Materials. Ice cubes, cups, timers, chocolate. 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. Make ice in advance.
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 ice and ask, “What will happen?”
Explanation (10 min). Teach melting.
Guided activity (10 min). Learners race ice.
Independent activity (10 min). Learners explain.
Assessment and reflection (5 min). Ask each learner to say one thing they learned and how they know it.
Key questions. What changed? Can it change back?
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. “Melting makes new material.” Same material.
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 melting and freezing. 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 8; 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.