You will need a thermometer to do this lesson.
Children should set up an investigation to find out the temperature that water changes state.
1. With an adult, boil some water to find out the temperature that water has to reach before it starts to evaporate.
2. Take some ice out of the freezer and leave it to melt. Regularly check the temperature of the ice / ice water to find out at what temperature ice starts to melt.
3. Leave the melted water in the room and keep checking its temperature. What is the highest the temperature to over 2 hours? Why won't it get any higher?
Watch https://explorify.wellcome.ac.uk/en/activities/whats-going-on/melting-ice-cubes (you’ll need to set up a free explorify account in advance). Write what is shown in the video and explain why – scientific reasoning more important than being correct.