• Quick retrieval from earlier learning (Weathering and erosion). Students answer on mini whiteboards.
• Show answers together and note who needs support in the main task.

1. Which type of weathering is this: rabbits burrowing into soft rock? (physical weathering / chemical weathering / biological weathering) → biological weatheringPrompt: Is it caused by temperature and ice, by a chemical reaction, or by living things?
2. Which landform is mainly carved by a river over a very long time? (a volcano / a sand dune / an island / a canyon) → a canyonPrompt: The Grand Canyon was cut by the Colorado River.
3. Which happens quickly rather than over a long time? (a river valley widening / a canyon forming / a mountain wearing down / a landslide) → a landslidePrompt: Some changes to Earth take seconds; others take millions of years.

• Pass round different rocks and ask how each one might have formed.
• Share the objective: Physical, chemical and biological weathering. Read the success criteria together.

• Work through the example out loud, saying why you do each step, not just what you do.
• Example: Which type of weathering is this: water freezes in a crack, expands and splits the rock?
• Step 1: Physical weathering breaks rock into pieces without changing its chemicals.
• Step 2: So the answer is: physical (freeze–thaw, heating and cooling)
• Answer: physical (freeze–thaw, heating and cooling)
• Pause after each step and ask a student to say what comes next.

• Do these together. Students try each step on whiteboards before you reveal it.
• Use the hints as prompts rather than giving the answer.

1. Which type of weathering is this: iron minerals in rock rust and crumble? (physical (freeze–thaw, heating and cooling) / chemical / biological) → chemicalPrompt: Is a living thing involved? Are new substances formed, or does the rock just break into pieces?
2. In which climate is freeze–thaw weathering most common? (under the sea / where temperatures often go above and below 0 °C / in a hot desert that never freezes / in a tropical rainforest) → where temperatures often go above and below 0 °CPrompt: Water must freeze and melt again and again.

• 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 6 questions are on the student sheet below, with answers in the key.

• Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.

1. Weathering and erosion: which statement is NOT true? (Weathering helps turn rock into soil. / Plant roots can split rocks. / Water shrinks when it freezes. / Rivers erode their banks and carry sediment.) → Water shrinks when it freezes.Prompt: What does water do when it freezes?
2. Old gravestones made of marble are often harder to read than those made of granite. Why? (Marble (calcium carbonate) is chemically weathered by acidic rain / Granite dissolves in rain / Marble is attacked by tree roots / Granite is softer) → Marble (calcium carbonate) is chemically weathered by acidic rainPrompt: Which rock reacts with acids?

Free online practice with hints and printable worksheets for this skill: eurekami.com/science/grade-6.