Test, Change, Improve

Overview

Lesson 12 of 15 in Playground Physics and Design. In teams, students investigate how one changed feature affects the movement and stability of an object on a ramp, then use evidence to improve a playground model or blueprint. The lesson emphasises fair testing, safe design, accessibility and communicating findings.

Learning intentions

• WALT plan and carry out a fair test by changing one variable at a time.
• WALT describe how ramp angle, length, object size, load or surface can affect speed, distance, stability and stopping.
• WALT record repeated results and represent them in a simple graph.
• WALT use evidence to revise a playground design for excitement, accessibility and safety.

Success criteria

• I can identify what I will change, measure and keep the same.
• I can carry out at least three safe, repeated tests and record results clearly.
• I can make a simple graph and describe a pattern in my results.
• I can explain one design change using evidence from my tests.

Curriculum links

• Investigating in science: asking questions, making predictions, carrying out fair tests, recording observations and using evidence.
• Physical world: exploring how pushes, slopes, surfaces and loads affect movement.
• Communicating in science: using tables, graphs, discussion and labelled drawings to share findings.
• Science and society: applying scientific ideas to design a playground that is exciting, inclusive, safe and controllable.

Lesson structure (45 minutes)

1. 0–5 minutes – Hook and purpose Open with the hook and lesson overview slides. Show two possible ramp designs and ask: “Which one would be more exciting? Which one would be safer and easier for everyone to use?” Briefly revisit the unit question: How can we design a playground that works well for different people?

2. 5–10 minutes – Fair-test briefing Use the fair-test instruction slides to model a ramp investigation. Explain that a fair test changes one feature only, while the ramp, starting point, object and measuring method stay the same. Introduce the terms change, measure and keep the same. Demonstrate safe handling: release objects, never push them, keep hands and faces clear, and stop if equipment becomes unstable.

3. 10–14 minutes – Team planning Place students in five teams of five and assign roles: equipment manager, launcher, timer or distance measurer, recorder and safety checker. Distribute the ramp investigation recording sheet. Each team chooses one variable: ramp angle, ramp length, object size, load or surface. They write a prediction and identify what will remain the same. Check plans before testing begins.

4. 14–27 minutes – Repeated fair tests Teams conduct three trials for each of two or three settings, depending on equipment. They measure an agreed outcome such as travel time, distance travelled, distance needed to stop or whether the object tips. Students record every result rather than relying on one trial. Circulate with the practical testing reminder slides, asking: “What is your evidence?” and “How are you keeping this test fair?”

5. 27–35 minutes – Graph and interpret Teams calculate or identify a simple typical result, such as the most common result or approximate average, and complete a labelled bar graph on the graph and interpretation section. Younger or less confident students may graph two settings only. Prompt teams to describe one pattern and one surprising result using sentence frames: “When we changed…, … happened because…”

6. 35–42 minutes – Revise the design Teams return to their model or blueprint and choose one evidence-based improvement. They add a labelled change, such as a gentler slope, a textured stopping area, a wider track, a smaller load or a handrail. The revision must balance excitement with control, safety and access for people with different abilities. Teams prepare a 30-second explanation using the design revision and sharing prompts.

7. 42–45 minutes – Share and reflect Invite two or three teams to share their result and design change. Finish with the plenary reflection slide. Students complete the final reflection on the worksheet: “Our evidence showed… Therefore, we changed… This makes the design safer, more accessible or more exciting because…”

Resources

• One slide deck: the investigation and design slides
• One worksheet per student or team: the ramp investigation recording sheet
• Cardboard or wooden ramps
• Books or blocks for changing ramp height
• Small objects of different sizes or masses
• Optional surfaces: smooth card, fabric, carpet or sandpaper
• Rulers or tape measures
• Stopwatches or classroom timers
• Masking tape, pencils and coloured pens
• Existing playground models or blueprints from the unit
• Safety goggles if objects may roll quickly

Assessment

• Observe planning and testing: can students identify the changed variable, measured outcome and controlled variables?
• Check the worksheet for repeated results, a correctly labelled simple graph and a statement describing a pattern.
• Listen to design explanations and assess whether the proposed revision is linked to evidence and considers safety, accessibility, excitement and control.

Differentiation

• Support: provide a choice of two variables, pre-labelled table headings and sentence frames. Pair students strategically and allow a teacher or buddy to read instructions.
• Support for EAL learners: demonstrate each role, use gestures and picture cues for fast, slow, far, near, stable and stop, and rehearse explanations orally before writing.
• SEN and motor support: offer a stable ramp, a larger object, a partner launcher and a non-timed distance investigation. Ensure clear pathways and reduce noise around testing areas.
• Extension: ask students to compare variation between trials, explain why repeated testing improves confidence, or design a second test to check whether their revision works.