R8: Ratio Linear Functions
4 detailed 50-minute lessons with teaching scripts, worked examples, parent guides, and assessment criteria.
Lesson Overview
Total Lessons: 4
Tier: Foundation and Higher
Duration: 50 minutes per lesson (200 minutes total)
Exam Boards: AQA, Edexcel, OCR, Eduqas, CCEA
Tier: Foundation and Higher
Duration: 50 minutes per lesson (200 minutes total)
Exam Boards: AQA, Edexcel, OCR, Eduqas, CCEA
Learning Objectives
- Master core concepts of ratio linear functions
- Apply to exam questions confidently
- Develop independent study skills
- Build cross-topic connections
Prerequisites
- Review R7 proportion
- Key vocab: key vocabulary for r8
- Basic skills: basic literacy and numeracy
Materials & Equipment
- Exercise book, coloured pens
- Scientific calculator
- Ruler, protractor, compass (if needed)
- Printed spec/textbook reference
- Internet for videos (see Resources)
Lesson 1: Introduction: Ratio Linear Functions
Duration: 50 minutes
Starter Activity (5 minutes)
Quick Recall
3 quick questions to activate prior knowledge about ratio linear functions. Use mini-whiteboard or paper.
Main Content (35 minutes)
Parent/Teacher Guide:
Before lesson: Read script below. Prepare materials. Pre-teach key vocab: R8.
If stuck: See Troubleshooting below. Break into smaller steps.
Extension: See Stretch & Challenge section.
Before lesson: Read script below. Prepare materials. Pre-teach key vocab: R8.
If stuck: See Troubleshooting below. Break into smaller steps.
Extension: See Stretch & Challenge section.
Teaching Script (35 mins):
Mins 0-5 - Hook: "Today: Ratio Linear Functions. Goal: by the end you can petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres, using the method shown step by step. Connects to proportion (R7/R10) because you'll reuse its method throughout today's work."
Mins 5-15 - Direct Instruction: 1) Define: "Ratio Linear Functions is..." 2) Key principle: "Most important:..." 3) Draw diagram, label live. 4) Real example: "Like Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres. - the same maths you already do when shopping or cooking..."
Mins 15-25 - Guided Practice: Ex1: Teacher models. Ex2: Student tries with guidance. Ex3: Student independent.
Mins 25-35 - Independent Practice: 3-5 questions. Immediate feedback.
Mins 0-5 - Hook: "Today: Ratio Linear Functions. Goal: by the end you can petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres, using the method shown step by step. Connects to proportion (R7/R10) because you'll reuse its method throughout today's work."
Mins 5-15 - Direct Instruction: 1) Define: "Ratio Linear Functions is..." 2) Key principle: "Most important:..." 3) Draw diagram, label live. 4) Real example: "Like Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres. - the same maths you already do when shopping or cooking..."
Mins 15-25 - Guided Practice: Ex1: Teacher models. Ex2: Student tries with guidance. Ex3: Student independent.
Mins 25-35 - Independent Practice: 3-5 questions. Immediate feedback.
Worked Example 1: Basic
Q: Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres.
- What is asked? Petrol
- Recall knowledge: Direct proportion ↔ y = kx ↔ straight line through the origin; Gradient = unit rate = the ratio (k : 1)
- Apply: k = 28/20 = 1.4 → C = 1.4L → 32 × 1.4 = £44.80
- Check: Check the units named in the question and sense-check the size of your answer.
- Answer: £44.80
Tip: "Show working - method marks > answer marks."
Worked Example 2: Multi-step
Q: y : x = 3 : 5. Write y in terms of x and find y when x = 45.
- Break down: Separate parts?
- Solve each: y = (3/5)x → y = 27 when x = 45
- Combine: The parts chain: each answer feeds the next step of the question.
- Final answer: M1 for the 3/5 multiplier, A1 for 27. Ratio-to-function: the gradient is first : second.
Worked Example 3: Data/Application
Q: y : x = 3 : 5. Write y in terms of x and find y when x = 45.
- Read data: Axes, units, scale
- Patterns: Trends, anomalies
- Explain: Why? Using ratio linear functions
- Conclude: Evidence-based
Common Questions & Troubleshooting
Q: "Why does Direct proportion ↔ y = kx ↔ straight line through the origi work this way?"
A: Analogy: "Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres.". Try re-draw the worked example from memory, then check it against the model answer.
A: Analogy: "Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres.". Try re-draw the worked example from memory, then check it against the model answer.
Q: "Wrong answers on calculations."
A: Checklist: units? formula? calculator mode? sig figs?
A: Checklist: units? formula? calculator mode? sig figs?
Q: "Can't remember key terms."
A: Flashcards (term front, def+diagram back). Spaced repetition: day 1, 3, 7.
A: Flashcards (term front, def+diagram back). Spaced repetition: day 1, 3, 7.
Q: "Exam wording confuses me."
A: Commands: Describe=what you see; Explain=reasons; Evaluate=pros/cons+judgement; Calculate=working+units.
A: Commands: Describe=what you see; Explain=reasons; Evaluate=pros/cons+judgement; Calculate=working+units.
Q: "Running out of time."
A: 1 mark/min. Skip hard, return. Attempt all - partial marks count.
A: 1 mark/min. Skip hard, return. Attempt all - partial marks count.
Assessment & Model Answers
Mastery Checklist:
- [ ] Define Ratio Linear Functions in own words
- [ ] Identify features in diagram
- [ ] Explain process step-by-step
- [ ] Apply to unfamiliar context
- [ ] Score 80%+ on past paper question
Model Answer: Past Paper Question
Q: Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres.
- 1 mark: [Key terminology]
- 1 mark: [Mechanism/process]
- 1 mark: [Application/example]
- 1 mark: [Evaluation - Higher]
Model response: "[Complete answer with expected detail/terminology]"
Why full marks: [What makes this strong]
Stretch & Challenge (Grade 8-9):
- Synoptic links: Connect to R7-proportion / R9-percentages
- Real-world: Research use in industry, medicine or research
- Advanced calc: Try a more challenging variant
- Critical: "Evaluate limitations of today's model"
- Research: Recent discovery on ratio linear functions, summarise 100 words
Plenary (5 mins)
Label the Diagram
Unlabelled diagram - write all parts in 1 min
Assessment Criteria
- Got it: Confident explanation + correct worked examples
- Getting there: Main points OK, needs support with detail
- Not yet: Confused on key concepts, needs reteaching
Lesson 2: Core Concepts: Ratio Linear Functions
Duration: 50 minutes
Starter Activity (5 minutes)
Review Previous Lesson
Quick recap: write 3 key points from last lesson on ratio linear functions. Use mini-whiteboard or paper.
Main Content (35 minutes)
Parent/Teacher Guide:
Before lesson: Read script below. Prepare materials. Pre-teach key vocab: R8.
If stuck: See Troubleshooting below. Break into smaller steps.
Extension: See Stretch & Challenge section.
Before lesson: Read script below. Prepare materials. Pre-teach key vocab: R8.
If stuck: See Troubleshooting below. Break into smaller steps.
Extension: See Stretch & Challenge section.
Teaching Script (35 mins):
Mins 0-5 - Hook: "Today: Ratio Linear Functions. Goal: by the end you can petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres, using the method shown step by step. Connects to proportion (R7/R10) because you'll reuse its method throughout today's work."
Mins 5-15 - Direct Instruction: 1) Define: "Ratio Linear Functions is..." 2) Key principle: "Most important:..." 3) Draw diagram, label live. 4) Real example: "Like Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres. - the same maths you already do when shopping or cooking..."
Mins 15-25 - Guided Practice: Ex1: Teacher models. Ex2: Student tries with guidance. Ex3: Student independent.
Mins 25-35 - Independent Practice: 3-5 questions. Immediate feedback.
Mins 0-5 - Hook: "Today: Ratio Linear Functions. Goal: by the end you can petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres, using the method shown step by step. Connects to proportion (R7/R10) because you'll reuse its method throughout today's work."
Mins 5-15 - Direct Instruction: 1) Define: "Ratio Linear Functions is..." 2) Key principle: "Most important:..." 3) Draw diagram, label live. 4) Real example: "Like Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres. - the same maths you already do when shopping or cooking..."
Mins 15-25 - Guided Practice: Ex1: Teacher models. Ex2: Student tries with guidance. Ex3: Student independent.
Mins 25-35 - Independent Practice: 3-5 questions. Immediate feedback.
Worked Example 1: Basic
Q: Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres.
- What is asked? Petrol
- Recall knowledge: Direct proportion ↔ y = kx ↔ straight line through the origin; Gradient = unit rate = the ratio (k : 1)
- Apply: k = 28/20 = 1.4 → C = 1.4L → 32 × 1.4 = £44.80
- Check: Check the units named in the question and sense-check the size of your answer.
- Answer: £44.80
Tip: "Show working - method marks > answer marks."
Worked Example 2: Multi-step
Q: y : x = 3 : 5. Write y in terms of x and find y when x = 45.
- Break down: Separate parts?
- Solve each: y = (3/5)x → y = 27 when x = 45
- Combine: The parts chain: each answer feeds the next step of the question.
- Final answer: M1 for the 3/5 multiplier, A1 for 27. Ratio-to-function: the gradient is first : second.
Worked Example 3: Data/Application
Q: y : x = 3 : 5. Write y in terms of x and find y when x = 45.
- Read data: Axes, units, scale
- Patterns: Trends, anomalies
- Explain: Why? Using ratio linear functions
- Conclude: Evidence-based
Common Questions & Troubleshooting
Q: "Why does Direct proportion ↔ y = kx ↔ straight line through the origi work this way?"
A: Analogy: "Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres.". Try re-draw the worked example from memory, then check it against the model answer.
A: Analogy: "Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres.". Try re-draw the worked example from memory, then check it against the model answer.
Q: "Wrong answers on calculations."
A: Checklist: units? formula? calculator mode? sig figs?
A: Checklist: units? formula? calculator mode? sig figs?
Q: "Can't remember key terms."
A: Flashcards (term front, def+diagram back). Spaced repetition: day 1, 3, 7.
A: Flashcards (term front, def+diagram back). Spaced repetition: day 1, 3, 7.
Q: "Exam wording confuses me."
A: Commands: Describe=what you see; Explain=reasons; Evaluate=pros/cons+judgement; Calculate=working+units.
A: Commands: Describe=what you see; Explain=reasons; Evaluate=pros/cons+judgement; Calculate=working+units.
Q: "Running out of time."
A: 1 mark/min. Skip hard, return. Attempt all - partial marks count.
A: 1 mark/min. Skip hard, return. Attempt all - partial marks count.
Assessment & Model Answers
Mastery Checklist:
- [ ] Define Ratio Linear Functions in own words
- [ ] Identify features in diagram
- [ ] Explain process step-by-step
- [ ] Apply to unfamiliar context
- [ ] Score 80%+ on past paper question
Model Answer: Past Paper Question
Q: Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres.
- 1 mark: [Key terminology]
- 1 mark: [Mechanism/process]
- 1 mark: [Application/example]
- 1 mark: [Evaluation - Higher]
Model response: "[Complete answer with expected detail/terminology]"
Why full marks: [What makes this strong]
Stretch & Challenge (Grade 8-9):
- Synoptic links: Connect to R7-proportion / R9-percentages
- Real-world: Research use in industry, medicine or research
- Advanced calc: Try a more challenging variant
- Critical: "Evaluate limitations of today's model"
- Research: Recent discovery on ratio linear functions, summarise 100 words
Plenary (5 mins)
Label the Diagram
Unlabelled diagram - write all parts in 1 min
Assessment Criteria
- Got it: Confident explanation + correct worked examples
- Getting there: Main points OK, needs support with detail
- Not yet: Confused on key concepts, needs reteaching
Lesson 3: Application: Ratio Linear Functions
Duration: 50 minutes
Starter Activity (5 minutes)
Review Previous Lesson
Quick recap: write 3 key points from last lesson on ratio linear functions. Use mini-whiteboard or paper.
Main Content (35 minutes)
Parent/Teacher Guide:
Before lesson: Read script below. Prepare materials. Pre-teach key vocab: R8.
If stuck: See Troubleshooting below. Break into smaller steps.
Extension: See Stretch & Challenge section.
Before lesson: Read script below. Prepare materials. Pre-teach key vocab: R8.
If stuck: See Troubleshooting below. Break into smaller steps.
Extension: See Stretch & Challenge section.
Teaching Script (35 mins):
Mins 0-5 - Hook: "Today: Ratio Linear Functions. Goal: by the end you can petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres, using the method shown step by step. Connects to proportion (R7/R10) because you'll reuse its method throughout today's work."
Mins 5-15 - Direct Instruction: 1) Define: "Ratio Linear Functions is..." 2) Key principle: "Most important:..." 3) Draw diagram, label live. 4) Real example: "Like Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres. - the same maths you already do when shopping or cooking..."
Mins 15-25 - Guided Practice: Ex1: Teacher models. Ex2: Student tries with guidance. Ex3: Student independent.
Mins 25-35 - Independent Practice: 3-5 questions. Immediate feedback.
Mins 0-5 - Hook: "Today: Ratio Linear Functions. Goal: by the end you can petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres, using the method shown step by step. Connects to proportion (R7/R10) because you'll reuse its method throughout today's work."
Mins 5-15 - Direct Instruction: 1) Define: "Ratio Linear Functions is..." 2) Key principle: "Most important:..." 3) Draw diagram, label live. 4) Real example: "Like Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres. - the same maths you already do when shopping or cooking..."
Mins 15-25 - Guided Practice: Ex1: Teacher models. Ex2: Student tries with guidance. Ex3: Student independent.
Mins 25-35 - Independent Practice: 3-5 questions. Immediate feedback.
Worked Example 1: Basic
Q: Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres.
- What is asked? Petrol
- Recall knowledge: Direct proportion ↔ y = kx ↔ straight line through the origin; Gradient = unit rate = the ratio (k : 1)
- Apply: k = 28/20 = 1.4 → C = 1.4L → 32 × 1.4 = £44.80
- Check: Check the units named in the question and sense-check the size of your answer.
- Answer: £44.80
Tip: "Show working - method marks > answer marks."
Worked Example 2: Multi-step
Q: y : x = 3 : 5. Write y in terms of x and find y when x = 45.
- Break down: Separate parts?
- Solve each: y = (3/5)x → y = 27 when x = 45
- Combine: The parts chain: each answer feeds the next step of the question.
- Final answer: M1 for the 3/5 multiplier, A1 for 27. Ratio-to-function: the gradient is first : second.
Worked Example 3: Data/Application
Q: y : x = 3 : 5. Write y in terms of x and find y when x = 45.
- Read data: Axes, units, scale
- Patterns: Trends, anomalies
- Explain: Why? Using ratio linear functions
- Conclude: Evidence-based
Common Questions & Troubleshooting
Q: "Why does Direct proportion ↔ y = kx ↔ straight line through the origi work this way?"
A: Analogy: "Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres.". Try re-draw the worked example from memory, then check it against the model answer.
A: Analogy: "Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres.". Try re-draw the worked example from memory, then check it against the model answer.
Q: "Wrong answers on calculations."
A: Checklist: units? formula? calculator mode? sig figs?
A: Checklist: units? formula? calculator mode? sig figs?
Q: "Can't remember key terms."
A: Flashcards (term front, def+diagram back). Spaced repetition: day 1, 3, 7.
A: Flashcards (term front, def+diagram back). Spaced repetition: day 1, 3, 7.
Q: "Exam wording confuses me."
A: Commands: Describe=what you see; Explain=reasons; Evaluate=pros/cons+judgement; Calculate=working+units.
A: Commands: Describe=what you see; Explain=reasons; Evaluate=pros/cons+judgement; Calculate=working+units.
Q: "Running out of time."
A: 1 mark/min. Skip hard, return. Attempt all - partial marks count.
A: 1 mark/min. Skip hard, return. Attempt all - partial marks count.
Assessment & Model Answers
Mastery Checklist:
- [ ] Define Ratio Linear Functions in own words
- [ ] Identify features in diagram
- [ ] Explain process step-by-step
- [ ] Apply to unfamiliar context
- [ ] Score 80%+ on past paper question
Model Answer: Past Paper Question
Q: Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres.
- 1 mark: [Key terminology]
- 1 mark: [Mechanism/process]
- 1 mark: [Application/example]
- 1 mark: [Evaluation - Higher]
Model response: "[Complete answer with expected detail/terminology]"
Why full marks: [What makes this strong]
Stretch & Challenge (Grade 8-9):
- Synoptic links: Connect to R7-proportion / R9-percentages
- Real-world: Research use in industry, medicine or research
- Advanced calc: Try a more challenging variant
- Critical: "Evaluate limitations of today's model"
- Research: Recent discovery on ratio linear functions, summarise 100 words
Plenary (5 mins)
Exam Question Speed Round
5 quick questions, 1 min each. Mark together.
Assessment Criteria
- Got it: Confident explanation + correct worked examples
- Getting there: Main points OK, needs support with detail
- Not yet: Confused on key concepts, needs reteaching
Lesson 4: Exam Practice: Ratio Linear Functions
Duration: 50 minutes
Starter Activity (5 minutes)
Review Previous Lesson
Quick recap: write 3 key points from last lesson on ratio linear functions. Use mini-whiteboard or paper.
Main Content (35 minutes)
Parent/Teacher Guide:
Before lesson: Read script below. Prepare materials. Pre-teach key vocab: R8.
If stuck: See Troubleshooting below. Break into smaller steps.
Extension: See Stretch & Challenge section.
Before lesson: Read script below. Prepare materials. Pre-teach key vocab: R8.
If stuck: See Troubleshooting below. Break into smaller steps.
Extension: See Stretch & Challenge section.
Teaching Script (35 mins):
Mins 0-5 - Hook: "Today: Ratio Linear Functions. Goal: by the end you can petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres, using the method shown step by step. Connects to proportion (R7/R10) because you'll reuse its method throughout today's work."
Mins 5-15 - Direct Instruction: 1) Define: "Ratio Linear Functions is..." 2) Key principle: "Most important:..." 3) Draw diagram, label live. 4) Real example: "Like Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres. - the same maths you already do when shopping or cooking..."
Mins 15-25 - Guided Practice: Ex1: Teacher models. Ex2: Student tries with guidance. Ex3: Student independent.
Mins 25-35 - Independent Practice: 3-5 questions. Immediate feedback.
Mins 0-5 - Hook: "Today: Ratio Linear Functions. Goal: by the end you can petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres, using the method shown step by step. Connects to proportion (R7/R10) because you'll reuse its method throughout today's work."
Mins 5-15 - Direct Instruction: 1) Define: "Ratio Linear Functions is..." 2) Key principle: "Most important:..." 3) Draw diagram, label live. 4) Real example: "Like Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres. - the same maths you already do when shopping or cooking..."
Mins 15-25 - Guided Practice: Ex1: Teacher models. Ex2: Student tries with guidance. Ex3: Student independent.
Mins 25-35 - Independent Practice: 3-5 questions. Immediate feedback.
Worked Example 1: Basic
Q: Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres.
- What is asked? Petrol
- Recall knowledge: Direct proportion ↔ y = kx ↔ straight line through the origin; Gradient = unit rate = the ratio (k : 1)
- Apply: k = 28/20 = 1.4 → C = 1.4L → 32 × 1.4 = £44.80
- Check: Check the units named in the question and sense-check the size of your answer.
- Answer: £44.80
Tip: "Show working - method marks > answer marks."
Worked Example 2: Multi-step
Q: y : x = 3 : 5. Write y in terms of x and find y when x = 45.
- Break down: Separate parts?
- Solve each: y = (3/5)x → y = 27 when x = 45
- Combine: The parts chain: each answer feeds the next step of the question.
- Final answer: M1 for the 3/5 multiplier, A1 for 27. Ratio-to-function: the gradient is first : second.
Worked Example 3: Data/Application
Q: y : x = 3 : 5. Write y in terms of x and find y when x = 45.
- Read data: Axes, units, scale
- Patterns: Trends, anomalies
- Explain: Why? Using ratio linear functions
- Conclude: Evidence-based
Common Questions & Troubleshooting
Q: "Why does Direct proportion ↔ y = kx ↔ straight line through the origi work this way?"
A: Analogy: "Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres.". Try re-draw the worked example from memory, then check it against the model answer.
A: Analogy: "Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres.". Try re-draw the worked example from memory, then check it against the model answer.
Q: "Wrong answers on calculations."
A: Checklist: units? formula? calculator mode? sig figs?
A: Checklist: units? formula? calculator mode? sig figs?
Q: "Can't remember key terms."
A: Flashcards (term front, def+diagram back). Spaced repetition: day 1, 3, 7.
A: Flashcards (term front, def+diagram back). Spaced repetition: day 1, 3, 7.
Q: "Exam wording confuses me."
A: Commands: Describe=what you see; Explain=reasons; Evaluate=pros/cons+judgement; Calculate=working+units.
A: Commands: Describe=what you see; Explain=reasons; Evaluate=pros/cons+judgement; Calculate=working+units.
Q: "Running out of time."
A: 1 mark/min. Skip hard, return. Attempt all - partial marks count.
A: 1 mark/min. Skip hard, return. Attempt all - partial marks count.
Assessment & Model Answers
Mastery Checklist:
- [ ] Define Ratio Linear Functions in own words
- [ ] Identify features in diagram
- [ ] Explain process step-by-step
- [ ] Apply to unfamiliar context
- [ ] Score 80%+ on past paper question
Model Answer: Past Paper Question
Q: Petrol cost is proportional to litres: 20 litres cost £28. Write the function and find the cost of 32 litres.
- 1 mark: [Key terminology]
- 1 mark: [Mechanism/process]
- 1 mark: [Application/example]
- 1 mark: [Evaluation - Higher]
Model response: "[Complete answer with expected detail/terminology]"
Why full marks: [What makes this strong]
Stretch & Challenge (Grade 8-9):
- Synoptic links: Connect to R7-proportion / R9-percentages
- Real-world: Research use in industry, medicine or research
- Advanced calc: Try a more challenging variant
- Critical: "Evaluate limitations of today's model"
- Research: Recent discovery on ratio linear functions, summarise 100 words
Plenary (5 mins)
Exam Question Speed Round
5 quick questions, 1 min each. Mark together.
Assessment Criteria
- Got it: Confident explanation + correct worked examples
- Getting there: Main points OK, needs support with detail
- Not yet: Confused on key concepts, needs reteaching
📝 Mark Scheme Guidance
How examiners mark R8: Read the command word carefully — State = one word/phrase (1 mark), Describe = pattern or detail (2 marks), Explain = reason with "because" (2–3 marks), Compare = similarities AND differences, Evaluate = both sides + conclusion. Method marks are awarded for correct working even if the final answer is wrong. Always show your working — unexplained answers score zero for AO2.
Success on R8 questions: Underline the command word, count the marks (one mark per point expected), and answer in the format the command word demands.
Board Notes & Revision Links
This lesson is examined by: AQA 8300 | Edexcel 1MA1 | OCR J560 | Eduqas C300 | CCEA M-units. Tier and paper details vary - always check your board's current specification.
Follow-up revision: A7-functions on GCSE Revise (notes, flashcards and auto-graded target tests for this exact topic).
📐 Reference Diagram
✏️ Draw-Along Instructions
Parent/teacher: Draw a bar divided into parts proportional to the ratio. Label each part with its value. Write the total above. The ratio tells you how many parts each person gets.
Display the reference diagram (or draw it live) while pupils copy. Check each label as it is added.
Homework & Consolidation
- Consolidation: Textbook end-of-topic questions (30 mins)
- Retrieval: 10 flashcards for key terms (15 mins)
- Exam practice: 2 past paper questions (20 mins)
- Extension: Research real-world application (optional, 30 mins)