lesson
How does a material behave?
1 · Learn
A solid keeps its own shape unless a force changes it. A liquid flows and takes the shape of the part of its container that it occupies. A gas spreads to fill available space.
These describe states, not whether a material is heavy or visible. Air is a mixture of gases even though you usually cannot see it. Sand pours, but each grain is a small solid.
2 · Worked example
I compare an ice cube, liquid water and air in a safe model. Water can exist in different states; state is not a permanent label for every sample of a substance.
3 · Your turn
Are individual dry sand grains liquid just because a pile can pour?
Check your answer
No. Each grain is solid; a collection of many small solids can pour.
4 · Apply your learning
Observe adult-selected safe solid and liquid samples. Use a diagram or controlled demonstration to discuss gases.
Adult guidance and safety
No tasting unknown substances or inhaling gases. Adults select equipment; do not trap gases in heated sealed containers.
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My observation notebook
With an adult, look at a safe real example or a checked photograph. Name the example and say which you used. Record what you actually notice. Do not taste plants or materials, approach unknown animals or invent missing observations.
Ask your teacher for support with the method and recording. A prediction is what you think might happen; an observation is what you actually see, hear or feel safely.
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No observations recorded yet. Look first, then add one.
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