Exploring Friction

Overview

This lesson is the third in the 9-lesson unit “Exploring Push and Pull Forces”. Students investigate how friction affects the motion of objects when a push or pull is applied, linking everyday experiences (sliding, stopping, gripping) to scientific explanations.

Learning intentions

WALT:

• Investigate how friction changes how far and how fast objects move when pushed or pulled.
• Identify forces acting on an object using everyday language and simple force-arrow ideas (direction and effect).
• Plan a fair test by keeping variables the same while changing only the surface.

Success criteria

Students can:

• Explain how friction slows, stops, or allows objects to move more when a push/pull is applied.
• Describe the effect of changing surfaces (e.g. rough vs smooth) on movement.
• Record results in a simple table and identify patterns in their data.
• Use safe investigation practices and equipment correctly.

Curriculum links

• AC9S4U03: identify how forces can be exerted by one object on another and investigate the effect of frictional, gravitational and magnetic forces on the motion of objects.
• AC9S4I02: use provided scaffolds to plan and conduct investigations, identifying the elements of fair tests and using equipment safely.
• AC9S4I04: construct and use representations (tables/graphs/models) to organise data, show simple relationships and identify patterns.
• AC9S4I01: pose questions, explore patterns/relationships and make predictions based on observations (e.g. which surface causes more stopping).

Lesson structure (total minutes)

1. 0–5 min · Hook (experience check). Teacher shows two short scenarios (e.g. “sled on sand vs smooth floor”, “toy car on carpet vs tile”) and asks: “Where would the push/pull have to work harder, and why?” Students do a quick think-pair-share and share one reason.

2. 5–12 min · Direct teach (forces and friction). Teacher introduces friction as a force that acts when surfaces rub, and explains that it can reduce movement from pushes/pulls (objects may slow down and stop). Teacher models a simple force-arrow diagram: push/pull forward, friction opposing motion. Students add one labelled force idea to their worksheet: “push/pull” and “friction acts opposite the motion”.

3. 12–15 min · Question & prediction. Teacher poses the investigation question: “How does surface roughness affect how far a pushed object travels?” Students make a prediction: “I think the object will move farther/shorter on ___ because ___.”

4. 15–30 min · Investigation (fair test). Teacher sets up a ramp or flat track (choose one for your classroom) with two or three interchangeable surfaces (e.g. tile, lino, sandpaper, carpet tile). Teacher provides a scaffold: choose one variable to change (surface), keep others the same (same object, same push strength method, same start position, same release). Students work in pairs at stations: each trial uses the same gentle “push technique” (or same drop distance if using a ramp) and measures distance travelled from start to stop. Students run multiple trials per surface and record in a table (surface | trial 1 | trial 2 | trial 3 | average).

• Safety reminder: hands clear of wheels/edges, careful use of tape/measuring, no throwing objects.

5. 30–38 min · Share patterns (data and explanation). Teacher prompts: “What pattern do you see? Which surface shows the most stopping and what does that tell us about friction?” Students calculate an average distance for each surface, then circle the biggest and smallest averages and make one sentence explaining the pattern.

6. 38–45 min · Exit ticket (apply to push/pull). Teacher gives an exit ticket with two prompts:

• “Explain how friction affects the effect of a push/pull in your investigation.”
• “If we used an even rougher surface, would the object move more or less? Why?” Students complete independently, then turn in.

Resources

• Track/ramp materials (sheet or strip track, metre ruler or measuring tape)
• Assorted surfaces (tile, lino, sandpaper sheets, carpet samples)
• Same object for all trials (toy car, puck on wheels, small block with a handle)
• Masking tape for consistent start line and measured stop area
• Clipboards or investigation worksheets with a table for results
• Marker pens, safety glasses (if using sandpaper or small projectiles/edges)
• Optional timer (only if needed; distance is the main measurement)

Assessment

• Teacher observes students during the setup, checking that the fair test scaffold is followed (one change: surface).
• Formative check during investigation: students can state what they changed and what stayed the same.
• Exit ticket assesses understanding of friction’s effect on push/pull and uses evidence from their measured pattern.

Differentiation

• Support: provide sentence starters for predictions and explanations (e.g. “I predict ___ because ___.” “Friction is stronger on ___, so the object ___.”). Give a “fair test checklist” at the station.
• Support: pre-teach and model measuring distance from start mark to stop point; include a diagram on the worksheet.
• Extension: challenge students to test a third surface or compare two objects (same size, different material) and discuss whether changing object material changes the pattern of friction.
• EAL/SEN: use visuals (force-arrow example, rough/smooth icons) and allow oral recording of observations before writing.
• Hands-on engagement: ensure all students handle surface changes and measure distances at least once during the station work.

Differentiation (for the teacher’s flow within 4 students)

• Rotate roles each trial: measurer, recorder, surface manager, safety checker. This keeps all learners actively participating and supports accurate, consistent measurement.