Solids, liquids and gases

Ages 6 to 8 Read together, then try alone · about 20 minutes

Read together

Matter is what everything is made of. It comes in three common forms.

A solid keeps its shape, such as ice. A liquid flows, such as water. A gas spreads out, such as steam.

Heat can change one form into another.

Do it

1. Sort things at home into solid, liquid and gas (air in a balloon, steam from a kettle, juice, a spoon). Ask a grown-up to show steam from a safe distance.
2. Put an ice cube in a bowl and watch it melt over an hour. Draw it each 15 minutes.
3. Put the water in the freezer and see it change again. Is it the same water?
4. Blow up a balloon. What is inside? Where does the air go when it leaks out?

Talk about it

• What changed the ice into water?
• Is air a gas?

For the grown-up

Water is the easy example: ice (solid), water (liquid), steam (gas). Melting and freezing can be reversed, which is a first look at physical change.

Mark as done

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Where this comes from

• NGSS Lead States, Next Generation Science Standards: For States, By States (National Academies Press, 2013), performance expectation 2-PS1-1 (describe and classify different kinds of materials by their observable properties)
• NGSS Lead States, Next Generation Science Standards: For States, By States (National Academies Press, 2013), performance expectation 2-PS1-4 (construct an argument that some changes caused by heating or cooling can be reversed and some cannot)

Written with AI assistance and checked against the sources listed. Please read it before sharing it with a child.