Science lesson plan · 2nd grade (Year 3 in England) · 45 minutes
What happens when we cool it?
States of matter
CCSS NGSS.2-PS1-4England: KS1 Y2 Uses of everyday materialsEngland: KS2 Y4 States of matter
Objective and success criteria
Students will: What happens when we cool it?.
- I can answer questions on today's skill on my own, without help.
- I can explain each step and say why it works.
- I can check my answer and spot a mistake.
Before and after
Needs first: Heating and cooling: can the change be undone?
Leads to: the next skill in this area.
Materials: Ice, water and a kettle (teacher demo), Particle diagrams, Mini whiteboards, A diagram or short video clip of the idea, Printed student sheet (below).
Warm-up · 5 min
- Quick retrieval from earlier learning (Heating and cooling: can the change be undone?). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- Can this change be undone: chocolate melting in a warm hand? (can change back / cannot change back) → can change backPrompt: Could you get the starting material back by warming it or cooling it?
- Three of these changes CAN be undone. Which one is different? (an ice lolly (popsicle) melting / chocolate melting in a warm hand / burning a log on a fire / candle wax melting) → burning a log on a firePrompt: Think about melting and freezing versus cooking and burning.
- Can you turn a fried egg back into a raw egg by putting it in the fridge? (Yes, if you wait a day. / Yes, cooling always undoes heating. / Yes, but only for brown eggs. / No, cooking made a change that cannot be undone.) → No, cooking made a change that cannot be undone.Prompt: Is a cooked egg white still see-through and runny?
Hook · 5 min
- Show an ice cube melting and a kettle steaming and ask what is the same and what is different.
- Share the objective: What happens when we cool it?. Read the success criteria together.
I do: model it · 10 min
- Work through the example out loud, saying why you do each step, not just what you do.
- Example: What happens when this cools down: hot candle wax left to cool?
- Step 1: So the answer is: turns back into solid wax
- Answer: turns back into solid wax
- Pause after each step and ask a student to say what comes next.
We do: guided practice · 10 min
- Do these together. Students try each step on whiteboards before you reveal it.
- Use the hints as prompts rather than giving the answer.
- What happens when this cools down: melted chocolate in the fridge? (freezes into ice / sets into a wobbly solid / turns back into solid wax / sets hard again) → sets hard againPrompt: Cooling often turns liquids into solids, and gases into liquids.
- Hot wax is poured into a candle mould. What must happen before you can take the candle out? (The wax must dissolve. / The wax must boil. / The wax must cool and become solid. / The wax must be heated more.) → The wax must cool and become solid.Prompt: Is liquid wax able to keep a shape?
You do: independent practice · 10 min
- Students work on the student sheet. Circulate and check the first two answers of every student early.
- Students who finish: write a question of their own for a partner, with the answer.
The 8 questions are on the student sheet below, with answers in the key.
Exit ticket · 5 min
- Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.
- What happens when this cools down: melted chocolate in the fridge? (turns into water droplets / sets hard again / turns back into solid wax / freezes into ice) → sets hard againPrompt: Cooling often turns liquids into solids, and gases into liquids.
- Why does a bathroom mirror steam up after a hot shower? (Warm, damp air cools on the mirror and forms tiny water drops. / Soap sticks to the mirror. / Light turns into water. / The mirror is melting.) → Warm, damp air cools on the mirror and forms tiny water drops.Prompt: Is the mirror warmer or cooler than the steamy air?
Watch out for
- Everyday meanings of words getting in the way of the science meaning: define key words explicitly.
- Remembering facts without the reason: ask "why?" and "what is the evidence?"
Support and stretch
Support
- Review first: Heating and cooling: can the change be undone?.
- Use concrete materials: ice, water and a kettle (teacher demo).
- Give the first step of each question, or a partly worked example to finish.
- Pair with a confident partner for the guided practice.
Stretch
- Explain a common mistake in writing and how to fix it.
- Write a word problem that uses today's skill, then solve a partner's.
Homework and more practice
Free online practice with hints and printable worksheets for this skill: eurekami.com/science/grade-2.
Free lesson plan from eurekami.com/lesson-plan-builder