Science · Year 2

Active learning ideas

Reducing and Increasing Friction

Active exploration helps students connect abstract ideas about friction to their own experiences with moving objects. When children test surfaces and materials themselves, they build lasting understanding of forces that act in daily life. These hands-on investigations make invisible forces visible and measurable.

• ACARA Content Descriptions
• AC9S2U03

• 25–40 min
• Pairs → Whole Class
• 4 activities

Activity 01

• Plan-Do-Review
• 35 min · Small Groups

Ramp Testing: Surface Variations

Build ramps from cardboard and test a block sliding down smooth wood, sandpaper, and fabric. Students predict speed, time descents with a stopwatch, and record which surface increases or reduces friction. Discuss results as a class.

Design an experiment to reduce friction on a sliding block.

Facilitation Tip

During Ramp Testing, remind students to keep the block’s starting point and push force the same for each surface to ensure fair comparisons.

What to look for

Give students a card with a picture of a bicycle. Ask them to write one sentence about where friction is reduced and one sentence about where friction is increased on the bicycle.

• Remember
• Apply
• Analyze
• Self-Management
• Decision-Making
• Self-Awareness

Activity 02

• Plan-Do-Review
• 30 min · Pairs

Wheel Challenge: Add or Remove Wheels

Provide blocks and toy wheels. Pairs attach wheels to one block and leave another plain, then race them down inclines. Measure distances traveled and note how wheels reduce friction. Repeat with added weight.

Analyze how oil helps reduce friction in a machine.

Facilitation Tip

For the Wheel Challenge, have students count wheels and note which arrangements slide fastest and which grip best to see the trade-off between speed and control.

What to look for

Present students with three objects: a toy car, a ramp covered in sandpaper, and a small bottle of oil. Ask students to predict which object will help a block slide fastest down the ramp and explain why, using the terms friction, lubricant, or surface.

• Remember
• Apply
• Analyze
• Self-Management
• Decision-Making
• Self-Awareness

Activity 03

• Plan-Do-Review
• 25 min · Small Groups

Oil Experiment: Lubricant Test

Set up trays with dry and oiled surfaces. Students slide small cars across both, timing motion and observing differences. Wipe and retest to confirm oil's role in reducing friction. Chart findings.

Justify why car tires have treads to increase friction.

Facilitation Tip

In the Oil Experiment, provide small droppers so students apply the same amount of oil to each ramp section, preventing uneven coverage that skews results.

What to look for

Pose the question: 'Why do we need friction sometimes, but want to reduce it other times?' Facilitate a class discussion, guiding students to provide examples for both reducing and increasing friction in everyday situations.

• Remember
• Apply
• Analyze
• Self-Management
• Decision-Making
• Self-Awareness

Activity 04

• Plan-Do-Review
• 40 min · Pairs

Tire Tread Model: Grip Stations

Create model tires from clay with smooth, grooved, and rough patterns. Roll them on wet paper towels and dry surfaces, rating grip levels. Students justify why treads increase friction for safety.

Design an experiment to reduce friction on a sliding block.

Facilitation Tip

When building Tire Tread Models, use masking tape on cardboard to create clear patterns students can compare side by side on the ramp.

What to look for

Give students a card with a picture of a bicycle. Ask them to write one sentence about where friction is reduced and one sentence about where friction is increased on the bicycle.

• Remember
• Apply
• Analyze
• Self-Management
• Decision-Making
• Self-Awareness

A few notes on teaching this unit

Teachers should emphasize that friction isn’t just present or absent, but varies by surface and condition. Avoid oversimplifying by showing students how even seemingly smooth surfaces create resistance. Research suggests children learn best when they test their own ideas, so frame activities as experiments where predictions can be wrong and that’s part of learning. Model how to record data in tables and use graphs to spot trends over time.

Successful learning looks like students using precise vocabulary, making predictions, collecting data, and explaining why friction changes with different surfaces or tools. They should connect their findings to real-world objects like bicycle brakes or skateboard wheels.

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Watch Out for These Misconceptions

• During Ramp Testing: Surface Variations, watch for students assuming only rough surfaces create friction.

  Pause the activity and have students feel the surfaces with their fingertips, then predict which will slow the block most. After testing, revisit their predictions to show that even glass causes friction that can be measured.

• During Wheel Challenge: Add or Remove Wheels, watch for students believing wheels remove friction entirely.

  Ask students to compare the time it takes for the block with and without wheels. Use their data to explain that wheels change sliding friction to rolling friction, which is still present but smaller.

• During Oil Experiment: Lubricant Test, watch for students thinking oil makes surfaces completely slippery.

  Have students apply oil to a small section of the ramp and compare its speed to a dry section. Discuss why some friction remains, linking it to microscopic surface interactions.

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Methods used in this brief

• Plan-Do-Review