Selecting and developing activities for finding forces

Teacher Tip: Based on the Physics Narrative and the Teaching and Learning Issues

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 Narrative to find these lines of thinking worked out and then look in the Teaching Approaches for some examples of activities.

Strategies for supporting learning

• draw on learners conception 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
• developed 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.