# Assembling a teaching strategy(Teaching tip)

### Constructing an electric circuit model

The pupils need to be able to picture what is going on as energy is shifted from battery to surroundings as the charged particles move around the circuit. That is, they need something to reason with that allows them to develop expectations about the behaviours of circuits that they've not yet met.

Teacher Tip: Develop, and make consist use of, a teaching model to support learning about intangible entities such as electrical current and energy.

Because you are dealing with objects and ideas that cannot be seen, electric circuits present an interesting teaching challenge.

We can think of two possible starting points for introducing the electric circuit model.

• A Direct approach: Develop an account based on a formal model of an electrical circuit.
• Using a teaching model: First introduce a teaching model for the electric circuit as a starting point for developing the formal electric circuit model.
• The advantage of using a teaching model is that it can provides a familiar, manipulable, tangible starting point for the pupils. The disadvantage is that an ill-chosen model may reinforce some wrong tracks, and not nudge pupils thinking down the right lines.

### Share tools for thinking with

Very often, analogies are drawn upon in teaching about electric circuits in an opportunist way, with the teacher perhaps briefly referring to the electric current as being, for example:

• Like the flow of water down a pipe.
• Like peas passing down a tube.
• Like pupils running down a corridor.
• We believe that this can be confusing and recommend a more systematic approach in which a teaching model is carefully introduced.

Teacher Tip: Make systematic use of a teaching model.

• Teacher: This is what happens when the circuit is completed: the bulb lights. How can we explain why this happens?

• Introduce the teaching model.
• Teacher: Let's think about something quite different: a loop of rope.

• Make links between model and circuit.
• Teacher: In what way is the rope loop similar to the electric circuit?

• Introduce the formal electric circuit model (through the teaching model).
• Teacher: We don't have rope moving around the circuit, but we do have charge.

• Continue to use the teaching model as needed.
• Teacher: So, why does the brightness of the bulb increase? You might want to go back to the rope loop in talking through your explanation.