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

1. How do scientists know about the inside of the Earth? (By studying how earthquake waves travel through it / By looking at the Moon / By visiting the core / By drilling to the centre) → By studying how earthquake waves travel through itPrompt: The deepest hole ever drilled is only about 12 km deep.
2. Earth's structure: which statement is NOT true? (The inner core is solid. / The mantle is the thickest layer. / The crust is the thickest layer. / Temperature increases as you go deeper into the Earth.) → The crust is the thickest layer.Prompt: Is the mantle really a sea of liquid?
3. Which layer of the Earth is liquid? (the inner core / the crust / all of them / the outer core) → the outer corePrompt: The inner core is solid because of huge pressure.

• Pass round different rocks and ask how each one might have formed.
• Share the objective: Plate tectonics, earthquakes and volcanoes. Read the success criteria together.

• Work through the example out loud, saying why you do each step, not just what you do.
• Example: Who first proposed that the continents drift?
• Step 1: Wegener's continental drift (1912) was later explained by plate tectonics.
• Step 2: So the answer is: Alfred Wegener
• Answer: Alfred Wegener
• 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. What evidence suggests the continents were once joined? (all continents are the same size / the oceans are salty / the same weather on every continent / matching fossils and rock layers on continents far apart) → matching fossils and rock layers on continents far apartPrompt: The same land reptile fossils are found in Africa and South America.
2. Two plates move apart at about 3 cm per year. How far apart will they move in 1 000 years, in kilometres? (1 km = 100 000 cm) → 0.03 kmPrompt: First find the distance in cm.

• 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 8 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. Plate tectonics: which statement is NOT true? (Mountains such as the Himalayas formed where plates collided. / The Earth's crust is broken into large pieces called tectonic plates. / Plates move a few centimetres each year. / Volcanoes only form in hot countries.) → Volcanoes only form in hot countries.Prompt: How fast do your fingernails grow? Plates move at about that speed.
2. Two plates move apart at about 3 cm per year. How far apart will they move in 1 000 000 years, in kilometres? (1 km = 100 000 cm) → 30 kmPrompt: First find the distance in cm.

Free online practice with hints and printable worksheets for this skill: eurekami.com/science/grade-7.