National Curriculum References
- KS3 Mathematics Programme of Study, Number, Ratio and Algebra, and Handling Data (DfE, 2014)
- Pupils should be able to:
- Interpret and construct tables and line graphs for given data, including distance-time and velocity-time graphs (Statistical methods 3)
- Solve problems involving speed, distance and time (Number 3)
- Use simple algebra to express problems mathematically and solve them (Algebra 2)
Learning Objectives
By the end of the lesson, pupils will be able to:
- Interpret distance-time graphs and understand what different shapes on the graph represent.
- Construct accurate distance-time graphs from given scenarios or data sets.
- Calculate the speed from a distance-time graph.
- Solve real-life contextual problems involving distance, time and speed using graphs.
Success Criteria
- I can describe what flat, sloped, and curved sections of a distance-time graph represent.
- I can plot a distance-time graph from a table of values.
- I can calculate speed (distance ÷ time) for sections of the graph.
- I can explain the motion of objects through information shown on a distance-time graph.
Lesson Structure (60 minutes)
1. Starter Activity (10 minutes)
Activity: Everyday motion brainstorm and prediction
- Show the class two images: one of a person walking steadily, one of a person standing still.
- Ask pupils to sketch a quick distance-time graph for each scenario from memory or intuition.
- Share selected predictions and briefly discuss.
- Teacher introduces how distance-time graphs represent motion at a glance.
Purpose: Activate prior knowledge and engage visualisation skills.
2. Introduction & Teaching Input (15 minutes)
Teaching Points:
- Explain axes: horizontal axis = time; vertical axis = distance.
- Describe:
- Flat line = stationary (distance not changing)
- Straight sloped line = steady speed (distance increasing linearly)
- Steeper slope = faster speed
- Curves = changing speed (acceleration/deceleration)
- Model drawing graphs from simple data tables (e.g., distance every 1 minute).
- Demonstrate calculating speed as gradient (Δdistance / Δtime) on straight sections.
Success Criteria Addressed: Understanding the graph features, plotting points.
Interactive Element:
- Pupils complete a mini whiteboard task: judge whether a given graph shows constant speed, stationary, or acceleration.
3. Guided Practice (15 minutes)
Activity: Constructing and interpreting graphs from data
- Provide pupils with data tables for scenarios (e.g., a jogger running with breaks, a car accelerating, a cyclist stopping).
- Pupils plot distance-time graphs in pairs on graph paper.
- Once complete, ask pairs to calculate speeds for different segments and describe the motion in their own words.
- Share a few examples with class discussion.
Teacher Role: Circulate, provide scaffolding, prompt with questions such as: “What does the flat section mean here?” or “How do you calculate speed in this section?”
4. Independent Application (15 minutes)
Main Task: Problem solving using distance-time graphs
- Give a worksheet of 3 contextual distance-time graphs showing different journeys (e.g., a train trip with stops, a person running and resting).
- Pupils answer questions: identify sections (stationary, constant speed, acceleration), calculate speeds, explain motions.
- Challenge pupils to draw their own graph based on a written scenario (e.g., a dog walks 20m in 4 minutes, rests 2 minutes, then runs 30m in 3 minutes).
5. Plenary & Formative Assessment (5 minutes)
- Exit ticket: each pupil writes a sentence answering: “What can a flat section on a distance-time graph tell us about an object's movement?”
- Collect responses and quickly address any misconceptions in next lesson.
Differentiation & Extension Activities
For Lower Attaining Pupils:
- Use pre-drawn graphs and focus on interpreting rather than drawing.
- Provide number lines and step-by-step calculation prompts for speed.
For Higher Attaining Pupils (Extension):
- Introduce graphs with negative slopes (return journeys).
- Challenge: Calculate average speed over the whole journey including stops.
- Challenge: Derive algebraic expressions for distance when speed and time are variables, linking to linear graphs y = mx + c.
- Explore the difference between distance-time and velocity-time graphs briefly and discuss why they look different.
Resources Needed
- Graph paper, ruler, pencil, eraser for each pupil
- Mini whiteboards and markers
- Printed data tables and worksheet with graphs and scenarios
- Visual aids for starter (images of walkers, runners)
- Exit ticket slips
Notes for Teachers
- Encourage pupils to verbalise their reasoning when interpreting graphs as this deepens conceptual understanding.
- Use real-life contexts relevant to pupils’ interests to make the concept tangible (e.g., sports activities, daily travels).
- Emphasise units in calculations: distance (m or km), time (s or mins), speed (m/s or km/h).
- Use technology if available: dynamic graphing software or interactive whiteboard to plot live graphs.
By delivering this lesson, pupils will have a solid foundation to progress to more complex kinematics and graph interpretation in GCSE maths.