Selecting and developing activities for finding forces
Classroom Activity
for 5-11
Things to think about when selecting and developing activities to aid the teaching of 'finding forces' based on the Physics Narrative and the Teaching Guidance.
Ideas to emphasise here
- Connect interactions between objects with the idea of a force
- Adopt consistent conventions about where and how the arrows are drawn
- Relate floating and sinking to forces, not to rules about displaced fluids
- Relate 'friction' to the mechanisms of friction
- Focus on the physical reasons for placing arrows
- Giving real experiences of forces acting at a distance
- Exploiting the tangible effects of magnets in regions of space around the magnet
- Relate electric, magnetic and gravity forces, without conflating them
- Separate the mass of an object from the force of gravity acting on the object, without being dogmatic
Teacher Tip: Work through the Physics Narratives to find these lines of thinking worked out and then look in the Classroom Activities for some examples of activities.
Strategies for supporting learning
- Draw on learners' conceptions of their own actions and relate these to force
- Explore and expose children's ideas of forces
- Draw out children's everyday ideas about motion and the forces required
- Introduce children to a new way of seeing – with forces
- Convince children that inanimate things can push, just like they can
- Develop the idea that a mechanism underpins the interaction that is replaced by force
- Convince children that air can exert forces
- Draw on children's own experience of action at the distance, probably through experiences with magnets
- Draw on children's experiences, some of which will be vicarious, to establish the reality of gravity in space
- Explore something of the mystery of action at a distance
Teacher Tip: These are all related to findings about children's ideas from research. The teaching activities will provide some suggestions. So will colleagues, near and far.
Avoid these
- Drawing arrows next two objects, or near objects, when you intend the force be acting on the object
- Don't act as if the placing of arrows is obvious and open to a simple inspection
- Don't refer to forces cancelling out
- Avoid using complex objects on which forces might be acting (with internally moving parts – bicycles, cars, people.)
- Using friction as a blanket term, without reference to its physical origins
- Treating contact forces exerted by inanimate objects as obvious
- Stating, without sharing the appropriate experiences that give the statements meaning
- Treating action at a distance as obviously acceptable
- Acting as if the similarities between the three non-contact forces always have been obvious
- Over-emphasising the similarities
- Conflating the terminology and representations for the three different forces
Teacher Tip: These difficulties are distilled from: the research findings; the practice of well-connected teachers with expertise; issues intrinsic to representing the physics well.