Teaching and Learning Resources p.1
tlr.nationalstrategies.dcsf.gov.uk
Helpful and unhelpful friction
Assessment focuses
AF1, AF2
Context
During a part of a lesson in which pupils investigated friction, one class group
identified different ways in which friction can be helpful or unhelpful. They drew
diagrams and annotated them to aid their explanations.
The pupils were asked to identify all areas of their chosen situations where they
considered friction would act, and explain a couple of these.
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Teaching and Learning Resources p.2
tlr.nationalstrategies.dcsf.gov.uk
The evidence
Un-useful friction: sled If there's too much friction then the sled won't move because it
can't slide with ease. Useful: Hand tricycle Friction between the chain and reel gives
it grip so it doesn't slip. Friction on the seat so you don't slip. Friction between the
wheel and the ground keeps it so the vehicle doesn't go too fast and slip.
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Teaching and Learning Resources p.3
tlr.nationalstrategies.dcsf.gov.uk
Teacher's notes
Zoe's comments showed that she could relate ideas about friction to various
technologies. She did not identify all areas on her sketches where she thought
friction would act, and this was something she initially found difficult to understand.
Zoe said that the arrows showed both the movement and the force. She could
describe how the friction worked against the direction the sledge was moving.
Next steps
• Discussion of why arrows are so useful for representing forces.
• Brainstorming the different ways in which arrows are used in scientific
diagrams and sketches.
Assessment commentary
Zoe can use models to help describe phenomena. She can link applications to their
underpinning scientific ideas, and use a scientific convention to communicate the
concept of force.
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