lesson
A rock's properties matter
1 · Learn
A rock's properties can make it useful for a job. A surface that wears away easily may not suit a busy step. A sample that absorbs water behaves differently from one that absorbs little.
A comparison should use similar-sized safe samples and the same method. A single classroom test gives evidence about those samples, not every rock everywhere.
2 · Worked example
In a fictional test, A absorbs more water than B. I can say B absorbed less in that test, but I cannot claim B will never let water through.
3 · Your turn
Why should both samples receive the same amount of water in an absorption comparison?
Check your answer
Otherwise the water amount, not just the rock sample, could explain a difference.
4 · Apply your learning
An adult demonstrates a small water-drop comparison on suitable samples. Record what actually happens.
Adult guidance and safety
Adult selects safe samples and manages water. Do not scratch valuable surfaces or use sharp tools.
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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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