Initial Teacher Education
To help you evaluate Electricity Explained for beginning teachers
18 lessons covering GCSE electricity in depth
Structured around GCSE Physics content so it’s easy to match to the syllabus, but aimed at a deeper understanding that you can’t find anywhere else.
Teaching simulations with the correct physics hard wired
Help students understand current, voltage and power visually. And it’s mathematically self-consistent, so you can time charges and it matches the measured current.
STOP! That looks like a donation model - we use the rope loop.
Okay, I understand - just bear with me, and let me walk you through my thinking…
The circuit simulation is a mathematical model with a visual output - it’s not an analogy
The visualisation has the same status as arrows representing forces.
Forces aren’t really arrows, but they help us see what’s going on, and it makes the maths easier.
I’m very explicit that we’re imagining energy like this, not saying what’s ‘really’ happening.
There is no mechanical analogue that is both accurate and simpler than just understanding circuits
This is my bold conjecture, based on thinking very hard about electricity for over 25 years.
The problem is modelling the response of power supplies.
They are constant voltage providers, that change the current they provide when the circuit changes.
Resistance is so hard to model mechanically because it’s already a rather dodgy metaphor
Resistance needs to tell two stories - one about flow and one about energy. The idea of electrical resistance is a metaphor invented to account for flow only.
Mechanical analogues, like friction in a rope loop, or pushing through crowds, or constrictions in pipes get the flow story right but not the energy story.
Batteries work less hard when resistance increases. They don’t struggle harder or keep their work rate constant - like we tend to do when we encounter a ‘resistance’.
The circuit simulation always gets the what happens right, without needing a story about why.
The simulation has no opinion about what resistance is or why increasing resistance causes the battery to provide a smaller current.
It just does the right thing when you make a change. This means you can easily see the answer to qualitative questions about change, without having to use maths, or an experiment, or translation from an analogous (supposedly) physical system.
I keep as close as possible to the spirit of the stores and pathways stories
I don’t talk about ‘electrical energy’, and I try and use the language of stores and pathways as closely as I can, within the bounds of the model.
But I know from experience that visualising the per-charginess of energy like this brings to life the meaning of potential - and how it’s connected to the rate at which energy is shifted - that teachers and students find immediately engaging and compelling.
Learners just get a nice experience - they don’t have to buy into a new philosophy
The eighteen lessons just quietly get on with getting the physics right.
Unlike other resources, I don’t say things that are wrong, and I do say some extra things that are helpful.
The fundamental ideas at the heart of the eighteen lessons
How batteries behave
Batteries are constant voltage providers. (They’re not constant current providers)
If you change the resistance in a parallel circuit the battery provides a different current. (It doesn't just ‘split’ differently)
Batteries run out of chemicals to react (physical) or their store of energy (theoretical). (They don't run out of electrons)
Resistance in simple circuits
Heating happens where the resistance is, but increasing the resistance causes less heating, not more. (Current doesn’t shift more energy ‘overcoming’ a higher resistance)
If you increase resistance, batteries work less hard, not harder. (Batteries don't struggle harder to try and reach some target current)
Sub-microscopic view
Charges make very slow progress, but are already there everywhere in the circuit, and start moving everywhere at almost exactly the same time. (They don't start from the battery and move quickly)
All changes to current or potential happen everywhere nearly instantly, not just connecting and disconnecting. (The speed of the charges is not the speed of the change)
Why would you care what I think?
Good question! As Jon Ogborn said to me during my PGCE - I wouldn’t say I’m an expert, but I’ve thought about it very hard.
I taught physics for ten years in west London, and the original incarnation of Electricity Explained, Furry Elephant, was used by schools all over the world for nearly twenty years.
I’ve been an expert reviewer of GCSE and A level physics for the OUP, and have led CPD for the IoP and ASE.
Teachers who are much cleverer and better at physics than I am tell me how much they get out of my resources, and how it helps them transform learning in the classroom.
This is me - Julian Hamm - at home in Devon.
Would you like to explore how this could help your students?
If you think it’s appropriate, I’d love to offer your students free access to all eighteen Electricity Explained lessons - to help with their own understanding, and to try it out at school if they like.
My vision is to transform the way teachers and students understand electricity, and it would be great if you thought it was something you might want to be part of.
(Equally, let me know why you think my ideas are dangerous nonsense that you wouldn’t let your students anywhere near!)
Things you could do while you ponder
Use the simulation for free
The simple circuit simulation comes with a complete set of resources to teach the basics of current, voltage and power. Use it for as long as you like.
Try the sample lesson with your students
The demo lesson on Measuring Current and I = Q/t is one of the eighteen lessons you get when you sign up. Why not see what your students think.