Science lesson plan · 10th grade (Year 11 in England) · 45 minutes
Seismic waves as evidence for Earth's layers
Earth and rocks
CCSS NGSS.HS-ESS2-3CCSS NGSS.SEP 7England: GCSE Physics: Waves (seismic waves, Physics only)
Objective and success criteria
Students will: Seismic waves as evidence for Earth's layers.
- I can answer questions on today's skill on my own, without help.
- I can explain each step and say why it works.
- I can check my answer and spot a mistake.
Before and after
Needs first: The structure of the Earth; Transverse and longitudinal waves
Leads to: the next skill in this area.
Materials: Rock samples, Hand lenses, Mini whiteboards, A diagram or short video clip of the idea, Printed student sheet (below).
Warm-up · 5 min
- Quick retrieval from earlier learning (The structure of the Earth; Transverse and longitudinal waves). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- Is this a transverse or a longitudinal wave: seismic P waves? (transverse / longitudinal) → longitudinalPrompt: Compare the direction of vibration with the direction the wave travels.
- How do scientists know about the inside of the Earth? (By drilling to the centre / By visiting the core / By looking at the Moon / By studying how earthquake waves travel through it) → By studying how earthquake waves travel through itPrompt: The deepest hole ever drilled is only about 12 km deep.
- Which layer of the Earth is liquid? (all of them / the outer core / the crust / the inner core) → the outer corePrompt: The inner core is solid because of huge pressure.
Hook · 5 min
- Pass round different rocks and ask how each one might have formed.
- Share the objective: Seismic waves as evidence for Earth's layers. Read the success criteria together.
I do: model it · 10 min
- Work through the example out loud, saying why you do each step, not just what you do.
- Example: At a seismometer, the S waves arrive 15 s after the P waves. Assume P waves travel at 8 km/s and S waves at 4 km/s. How far away was the earthquake, in km?
- Step 1: 1/4 − 1/8 = 1/8 s per km
- Step 2: 15 ÷ (1/8) = 120
- Step 3: So the answer is: 120 km
- Answer: 120 km
- Pause after each step and ask a student to say what comes next.
We do: guided practice · 10 min
- Do these together. Students try each step on whiteboards before you reveal it.
- Use the hints as prompts rather than giving the answer.
- At a seismometer, the S waves arrive 5 s after the P waves. Assume P waves travel at 8 km/s and S waves at 4 km/s. How far away was the earthquake, in km? → 40 kmPrompt: Each kilometre takes 1/4 s for S waves and 1/8 s for P waves.
- S waves are not detected on the opposite side of Earth from an earthquake. What does this show? (S waves are faster than P waves / Part of the core is liquid, because S waves cannot travel through liquids / The core is hollow / The crust is liquid) → Part of the core is liquid, because S waves cannot travel through liquidsPrompt: S waves are transverse.
You do: independent practice · 10 min
- 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.
Exit ticket · 5 min
- Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.
- At a seismometer, the S waves arrive 15 s after the P waves. Assume P waves travel at 8 km/s and S waves at 4 km/s. How far away was the earthquake, in km? → 120 kmPrompt: Each kilometre takes 1/4 s for S waves and 1/8 s for P waves.
- Inside the Earth: which statement is NOT true? (P waves can travel through solids and liquids. / S waves can only travel through solids. / Studying seismic waves lets scientists "see" inside Earth. / S waves are longitudinal.) → S waves are longitudinal.Prompt: How deep is the deepest hole ever drilled?
Watch out for
- Everyday meanings of words getting in the way of the science meaning: define key words explicitly.
- Remembering facts without the reason: ask "why?" and "what is the evidence?"
Support and stretch
Support
- Review first: The structure of the Earth.
- Use concrete materials: rock samples.
- Give the first step of each question, or a partly worked example to finish.
- Pair with a confident partner for the guided practice.
Stretch
- Explain a common mistake in writing and how to fix it.
- Write a word problem that uses today's skill, then solve a partner's.
Homework and more practice
Free online practice with hints and printable worksheets for this skill: eurekami.com/science/grade-10.
Free lesson plan from eurekami.com/lesson-plan-builder