# Introducing current to Year 7 - good demos, please!

Discussion in 'Science' started by lindsaygii, Mar 22, 2011.

1. ### lindsaygiiNew commenter

I have a willing but low ability - and very small - Year 7 set, about to start on currents.

I really want to set out by establishing what a current actually is, and I'm thinking of using the rope demo, but I'd like to do something with them on their feet 'moving the energy' themselves.

The group is 15 kids (when they all turn up), I'd like to do something along the lines of the 'passing the energy along the line', but I've never done it and can't quite imagine how it works in practice.

Can anyone help me with logistics/ repertoire of this demo, or suggest something else entirely, please?

Thank you.

2. ### stusing100

For electricity concepts I have had the students moving round the room and picking up sweets and moving with them to components. This works well and they can end up eating the sweets at some point (if not in a lab)
There are some really good analagies that you can find
Pizza/bread delivery truck
I like the elephants that the head of Phsics in on of my PGCE placement schools in south wales showed me

3. ### steve_cookeNew commenter

It is very hard to teach current separate from voltage, especially as the kids may well have heard of voltage and volts but probably haven't heard of amps. Just take them outside and get them running in a circle, take some stools to mark the circle out, have someone counting how many go by in a set time to act as an ammeter, the faster they run the higher the current and the hotter everything gets.

You can discuss the circle being broken leading to the current stopping, with a larger group you can even do parallel circuits with more than one intersecting loop of runners.

If you've got the kit, an ammeter, a 12V variable supply and a 10cm piece of nichrome wire on croc clips on a heat proof mat will relate back to what you've been saying, because as you push the current up the nichrome will heat up to red hot (700degC) and eventually yellow (about 900degC) before oxidising and falling apart, breaking the circuit. My 7s love this especially if you use the hot wire to burn through some paper.