Homeschool Guide: These lesson plans are a guide for parents. Content may contain errors — always cross-reference with official exam board specifications.

geological time & stratigraphy

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4 detailed 50-minute lessons with teaching scripts, worked examples, parent guides, and assessment criteria.

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Lesson Overview

Total Lessons: 4
Tier: Foundation and Higher
Duration: 50 minutes per lesson (200 minutes total)
Exam Boards: AQA, Edexcel, OCR, Eduqas, CCEA

Learning Objectives

Prerequisites

Materials & Equipment

Lesson 1: Introduction: geological time & stratigraphy

Duration: 50 minutes

Starter Activity (5 minutes)

Quick Recall

Write down everything you already know about geological time & stratigraphy. Then check against the key terms: key terms from geological time & stratigraphy. Use a mini-whiteboard or paper.

Main Content (35 minutes)

Parent/Teacher Guide:
Before lesson: Read the script below. Pre-teach key vocab: key terms from geological time & stratigraphy.
If stuck: Re-read the revision notes (link above), then break the content into smaller steps.
Extension: See the Stretch & Challenge ideas in Lesson 4.
Teaching Script (35 mins):
Mins 0-5 - Hook: "Today: geological time & stratigraphy. By the end you will be able to answer exam questions on it unaided. It connects to the rest of Geology because the ideas here recur across the spec."
Mins 5-20 - Direct Instruction: Work through the core ideas below one at a time; after each, ask your student to explain it back in their own words.
Mins 20-30 - Guided Practice: Model the worked example together, then let your student attempt the first practice question with guidance.
Mins 30-35 - Independent Practice: 2-3 practice questions from Lesson 3 below, with immediate feedback.
First Look

Start with the revision notes summary, then attempt: explain the key ideas of geological time & stratigraphy

Plenary (5 minutes)

Check Out

Your student states one thing they learned and one question they still have about geological time & stratigraphy.

Lesson 2: Core Concepts: geological time & stratigraphy

Duration: 50 minutes

Starter Activity (5 minutes)

Review Previous Lesson

Quick recap: write 3 key points from Lesson 1 on geological time & stratigraphy. Check them against the notes below.

Main Content (35 minutes)

Key Fact: The geological timescale divides Earth's 4.6 billion year history into eons, eras, periods and epochs
Key Fact: Principle of superposition: in undisturbed sequences, the oldest rocks are at the bottom and youngest at the top
Key Fact: Principle of original horizontality: sedimentary rocks are deposited horizontally; tilting indicates later deformation
Key Fact: Principle of cross-cutting relationships: a feature that cuts another is younger than what it cuts
Key Fact: Relative dating puts rocks in order of age; absolute (radiometric) dating gives a numerical age in millions of years
Key Fact: Index fossils are organisms that lived for a short time but were widely distributed, used to correlate rock layers across regions

Practice (10 minutes)

Q: explain the key ideas of geological time & stratigraphy

Answer:

Plenary (5 minutes)

Explain Back

Your student teaches the key points back to you without looking. Fill any gaps immediately.

Lesson 3: Application: geological time & stratigraphy

Duration: 50 minutes

Starter Activity (5 minutes)

Quick Recall

Recall the key terms: key terms from geological time & stratigraphy. Define each in one sentence.

Main Content (35 minutes)

Parent/Teacher Guide: Let your student attempt each question alone first, then compare with the model answer. Award method marks for correct working even if the final answer is wrong.

Work through the practice questions on the revision notes page for this topic.

Plenary (5 minutes)

Error Review

Review any questions answered incorrectly. Identify whether the error was knowledge, method, or reading the question.

Lesson 4: Exam Practice: geological time & stratigraphy

Duration: 50 minutes

Starter Activity (5 minutes)

Command Words

Review what these command words require: state (one point), describe (say what happens), explain (say why), compare (both sides), evaluate (judgement).

Main Content (35 minutes)

Exam-Style Question

Attempt a past-paper style question on geological time & stratigraphy from the exam board past paper finder (see Resources), then mark it against the scheme.

Exam Tips: Three stratigraphic principles: superposition, original horizontality, cross-cutting | Index fossil criteria: short range, wide distribution, recognisable, abundant | Radiometric dating: parent/daughter ratio + half-life = absolute age | Relative dating = order only; Absolute dating = numerical age in years
Common Errors: ✗ Superposition applies to all rock types ✓ Superposition applies to SEDIMENTARY and volcanic rocks deposited in layers; it does not apply to intrusive igneous rocks or metamorphic rocks that have been restructured ✗ Radiometric dating can be used on any rock ✓ Radiometric dating requires minerals with suitable radioactive isotopes; sedimentary rocks cannot be directly dated (they give the age of the source material, not deposition); igneous and metamorphic minerals are typically used ✗ The geological timescale is based on radiometric dating alone ✓ The timescale was originally built using relative dating (fossils and stratigraphy); radiometric dating later provided absolute ages to calibrat
Stretch & Challenge (Grade 8-9):
  • Synoptic links: explain how geological time & stratigraphy connects to another Geology topic you have studied
  • Real-world: research one real-world use or example of geological time & stratigraphy
  • Critical: "What are the limitations of the models used in geological time & stratigraphy?"

Plenary (5 minutes)

Assessment Criteria
  • Got it: Confident explanation + correct worked examples
  • Getting there: Main points OK, needs support with detail
  • Not yet: Confused on key concepts - re-run Lesson 2

Homework & Consolidation

Recommended Resources

🎓 Smart Lesson (Guided)