Firstly, we are going to take a look at why we teach electricity at GCSE. Then the content typically required in the new GCSE specifications. Finally we will be thinking about how this can be made engaging and relevant to all our students.

## Why?

We are all used to using electrical devices in everyday life without a second thought. We take them for granted, and are happy assuming they will work as expected. Hands up if you have had a student desperately begging you to let them charge their phone in your lesson because they ‘neeeeed’ it on the bus home? The aim of teaching the electricity topic is to help the students understand why their battery is ‘flat’ and how ‘charging’ makes their phone work again. Chances are there will not (sadly) be many future engineers in you class, but this topic has the potential to spark (sorry!) interest in electrical and electronic design. At the very least, the next generation should be leaving school with a functional literacy in how electrical devices work.

The other aspect of this topic is the thorny issue of which resources we should/could be using to generate our electricity now and in the future. We have an obligation to the planet here. The decisions our students will be making regarding sustainable resources have their foundations laid in the information laid before them in our classrooms.

## What?

The electricity topic is a bit of a behemoth. There are 6 main areas of study.

• Component characteristics. The symbols, conventions and reasons for drawing circuit diagrams are a familiar place to start. Most students have met the ideas here, but will not have met all the different components. The characteristics of fixed and variable (LDRs and Thermistors) resistors, diodes and filament bulbs are explained and students are expected to recognise and interpret V-I graphs for them.

• Current, Potential Difference and Resistance in series and parallel circuits. OK, this is something that even A-Level students find difficult to get to grips with. Things have improved in that the new specifications no longer expect students to work with parallel circuits when making calculations (only ‘simple’ series circuits according to the spec.). So no more working out effective resistances in parallel. Phew.

• Uses of domestic electricity. Students are learning about the ways in which electrical devices transfer electrical energy into other forms. Following on, how this relates to the power of the device.

• Distribution of domestic electricity. Just the basics about transformers are touched on here, and how they make the National Grid more efficient. The design/operation of transformers is looked at in more detail in the Magnetism topic.

• Global/national energy resources. There is no need to teach how electricity is actually generated in power stations. The emphasis is on teaching how the different resources affect the environment and local habitats. Moral and ethical implications are also a point of emphasis.

• Static charge and electric fields (Triple Physics Only). Static is one of the more fun aspects of the topic, engaging a class with the Van de Graaff generator provides a life-long memory for every one.

## How?

Electricity is an area which students find conceptually difficult and are arriving at with numerous misconceptions. Additionally girls are significantly harder to actively engage in the topic, because they can not see the relevance or importance.

• In teaching the topic regarding the National Grid, by far the most engaging I have experienced (with all abilities) is asking students to build their own model. With lower ability the key elements can be provided as cut out models, the more creative/dextrous can design and construct their own.

• The use of resources to generate electricity lends itself easily to some sort of project.

• This could be an individual research based project with a clear set of criteria for students to research, whether electronically or using resources provided in the classroom.

• Potentially, a group-work task could yield interesting results. Perhaps try setting each group a challenge to deliver electricity in different scenarios; the moon, the desert, in the middle of the ocean, up a mountain, in the jungle. There are countless situations that they could then report back on, either verbally or in written format.

• Alternatively, groups could be asked to deliver news reports on the development of an imaginary new electricity generation plant and the impact it will have.

• If you have a creative cohort you could ask groups to construct models of how different resources are used and then explain them to the class. If you are really ambitious, the models could be set up as a ‘science fair’ type of display for the whole school to look at one lunch-time.

• The behaviour of series and parallel circuits does provide ample scope for practical work. This can be instructional after establishing a firm grasp of the concepts, but launching straight into it can leave students feeling confused and frustrated. Oft times, the equipment does not work as expected and with 30+ inexperienced students building circuits, it can be impossible to fault trace all the circuits at once. If you are ready to embark on practical work, it is always worth considering splitting the class into two or three groups. If there are three tasks to complete and only one of them is a practical investigation, it is easier for you to solve the issues that those building circuits are having. Investigating the characteristics of components is a Required Practical so you wont be able to get away without letting your students loose on the equipment at some point though!

GCSE Electricity – Ideas on Making it Relevant