Last night I moderated (if that is the appropriate term) a discussion about teaching electricity which made for very interesting reading. I’ve posted a summary of the chat below, and as with all #ASEchat sessions, the official archive and summary can be found on the official #ASEchat page. I maintain an unofficial archive of #ASEchat transcripts on Google Docs in spread sheet format which allows you to sort by contributor, highlight links etc. The electricity chat can be found here.
Summary of Topic 24 – Teaching Electricity
I chose this topic as a biologist because I’m not sure I always do it justice. I wanted to hear from experienced and creative physicists how they introduce the concepts and any models they might use. I’ve listed some of these below:
- The Rope Model: recommended by the IoP and several ASEchat participants, the rope model can be used to model flow of charge around the circuit (several participants didn’t like the phrase ‘flow of current’). For those who haven’t seen this model before, this video captured at a regional ASE workshop (featuring Helen Pollard from the IoP) demonstrates how it works.
- The penguin rollercoaster was mentioned more than once (similar to this one) in which @gwiff explained the penguin is the charge, the height is the voltage, the current is the penguins going past, the resistance is the friction and finally the battery is the escalator.
- Several teachers said they introduce the term coulombs early on in KS3 and to specifically avoid referring to electrons. @Lethandrel said “Coulombs given joules each (EMF) Mission give them all away (pd is each charitable donation) Must do it in conga line” and shared an image of her own furry coulomb.
- Several teachers pointed out that many of the models have flaws in them (credit to @alomshaha and @informed_edu for pointing out the flaws in the rope model). All is not lost however as other contributors suggested that discussing models and their limitations fits in very well with ‘how science works’. In fact @alomshaha points out “It was while struggling with electricity as a student myself that I first really understood what a model was in science”.
- Primary teachers have a part to play in teaching electricity. Advice included avoid referring to electrons, don’t teach students that current decreases round a circuit, make circuits and test for breaks in these circuits, testing different sized batteries.
- Finally the question was asked if electricity is taught poorly in many instances, are we not better off leaving teaching electricity until KS4 so it can be taught by subject specialists. The response was mixed, however physicists are in short supply and many schools don’t have this luxury, so good models and explanations are essential for all teachers.
ViciaScience: Is teaching electricity just about understanding how bread is transported from bakery to supermarket?
Lethandrel: Avoid talking about electrons – kids end up obsessed and can’t think of electricity without them
Lethandrel: I talk about coulombs per sec and joules per coulomb, cute furry creature with bag of jewels/joules nice visual to hang it on
Agittner: have we all seen John Travoltage on the Phet simulations?
informed_edu: pet hate: "current flows round the circuit"
informed_edu: @Bio_Joe Charge flows around the circuit. Current is the number of coulombs flowing past each second.
alomshaha: @asober The IOP’s rope model is inadequate. Does not explain potential difference or drop in P.D across resistor
Useful links mentioned in the discussion
PhET Interactive Simulations – http://phet.colorado.edu/en/simulations/category/physics
Squishy circuits – http://courseweb.stthomas.edu/apthomas/SquishyCircuits/index.htm
Teaching Science for Understanding (Electricity) – http://www.education.leeds.ac.uk/research/cssme/ElecCircuitsScheme.pdf
Klunky Schematic Editor – http://www.qsl.net/wd9eyb/klunky/
Switched On Kids – http://www.switchedonkids.org.uk/
Hilary Osoko has advice for Primary teachers – http://www.tes.co.uk/article.aspx?storycode=96600
Making sense of children’s ideas http://staff.science.uva.nl/~joling/vakdidactiek/documenten/electricity.pdf