Squishy Circuits

Yesterday I retweeted a tweet for a Squishy Circuits project page and mentioned I had done it as a holiday activity.

After the retweet, I had a number of people ask me about the holiday science session where we used Squishy Circuits with children aged 5 and 6.

The idea is that you make two types of playdough: one that conducts electricity; the other insulates.

I started by introducing the idea that electricity needs to flow.  We looked at a large 6 volt battery, and connected it up to a light, making emphasis on the two wires needed: one to take the electricity to the light, and the other back, making a circuit.

Then I introduced the idea that electricity flows along material we call a conductor, and is stopped by material we call an insulator.

We tried connecting into the circuit wood, wire, and a pencil.  (The pencil is interesting, as the outside is insulating, but the graphite lead is conducting.)

“So guys, electricity needs to flow in a circuit.  It flows through conductors.  It is stopped by insulators.  Let’s play with playdough!”

We had green conducting playdough, and white playdough as insulating.  We also used LEDs, which meant we also needed to get across the concept that electricity needs to flow through it in one direction for it to emit light.  Ideally, I would have liked a light that could be put into the circuit either direction.  But LEDs are small, cheap, and light up at a small voltage.

We moved over to tables set up in a horseshoe.  This way the kids could see some large cardboard diagrams I was drawing up.  The first circuit we made got across the idea of the green vs the white:

In this circuit we put in many LEDs, and try them in different orientations to get across the idea that they will only work one way.

Next, I presented a couple of challenges.  One was a caterpillar:

I didn’t give them the colours of the dough they should use.  I left it up to them to figure out.  After giving them some thinking and construction time, I coloured in the answer:

The second challenge was to make a face with LEDs for eyes (an uncoloured outline of the next picture.)

Again, I gave them thinking and construction time, then showed the answer:

The rest of the session was freeplay where everyone could make their own model.  There were many monsters constructed.

My son Gabriel connecting up a squishy circuit.

Considering the age group, I found this was a great introduction to electrical circuits, conduction and insulation.  The playdough made for a kind of freeplay you couldn’t do with just wires and batteries.

Given further sessions, you could reinforce the concepts with more models and challenges.  More advanced session could include other electronic components, such as motors.

Any suggestions?

An Evening of Rough Science 2011

I have a rough video of last year’s An Evening of Rough Science.

Incidentally, I am looking for a camera person (people) for this year’s An Evening of Rough Science in August. If you know someone, contact me!