Science lesson plan · 2nd grade (Year 3 in England) · 60 minutes
Melting, freezing, evaporating and condensing
States of matter
CCSS NGSS.2-PS1-4CCSS NGSS.5-PS1-1England: KS2 Y4 States of matter
Objective and success criteria
Students will: Melting, freezing, evaporating and condensing.
- 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: Solids, liquids and gases
Leads to: Temperatures of water changing state; The water cycle; Heating and cooling: can the change be undone?
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 · 6 min
- Quick retrieval from earlier learning (Solids, liquids and gases). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- Is steam (water vapour) a solid, a liquid or a gas? (solid / liquid / gas) → gasPrompt: Does it keep its shape, flow, or spread out to fill a space?
- Sand can be poured like a liquid. Why is sand a solid? (It is found at the beach / It is yellow / Each grain keeps its own shape / It is wet) → Each grain keeps its own shapePrompt: Look at one grain with a magnifying glass.
- Is oxygen a solid, a liquid or a gas? (solid / liquid / gas) → gasPrompt: Does it keep its shape, flow, or spread out to fill a space?
Hook · 6 min
- Show an ice cube melting and a kettle steaming and ask what is the same and what is different.
- Share the objective: Melting, freezing, evaporating and condensing. Read the success criteria together.
I do: model it · 12 min
- Work through the example out loud, saying why you do each step, not just what you do.
- Example: Which change of state is this: melted wax going hard again?
- Step 1: Freezing is a liquid turning into a solid when it is cooled.
- Step 2: So the answer is: freezing
- Answer: freezing
- Pause after each step and ask a student to say what comes next.
We do: guided practice · 12 min
- Do these together. Students try each step on whiteboards before you reveal it.
- Use the hints as prompts rather than giving the answer.
- Which change of state is this: drops forming on a cold can taken from the fridge? (melting / freezing / evaporating / condensing) → condensingPrompt: What state does it start in, and what state does it end in?
- What is the name for a change from gas to liquid? (melting / freezing / evaporating (or boiling) / condensing) → condensingPrompt: Heating makes solids melt and liquids evaporate.
You do: independent practice · 17 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 · 7 min
- Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.
- What is the name for a change from gas to liquid? (evaporating (or boiling) / freezing / condensing / melting) → condensingPrompt: Heating makes solids melt and liquids evaporate.
- Changes of state: which statement is true? (The water on the outside of a cold can leaks through the metal. / Melting makes a substance lose mass. / Cooling can make a gas condense into a liquid. / Water only evaporates when it boils.) → Cooling can make a gas condense into a liquid.Prompt: Where does the water on a cold can come from?
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: Solids, liquids and gases.
- 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
- Move on to: Temperatures of water changing state; The water cycle; Heating and cooling: can the change be undone?.
- 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