How to Explain Electricity to Kids

Electricity is hard to explain because you cannot see it. The best approach is to stop describing it and let children build a loop that lights a bulb. Once they have found the loop for themselves, the words make sense.

First, the safety rule

Children only ever experiment with batteries, such as AA or D cells, and small torch bulbs. Never with mains outlets, plugs, extension leads or anything plugged in. Mains electricity can seriously hurt or kill. Say it plainly and early: “We only use batteries to play with electricity. Never put anything in a wall socket.” Keep rechargeable power packs and button batteries away from young children.

The idea in one sentence

Electricity is a flow of tiny charged particles around a complete loop, carrying energy from a battery to something that uses it, like a bulb. A gap anywhere in the loop stops the flow.

A water analogy helps for older children: a battery is like a pump, wires are like pipes, and the bulb is like a water wheel. It is not perfect, but it gives the right sense that something must go round and come back.

For ages 5 to 7: find the loop

Give your child a torch bulb, a battery and some wire or foil strips, and ask them to light the bulb. It may take several tries. Let them struggle a little. The bulb has two contact points (the side and the bottom), and the battery has two ends. When each end of the battery is connected to a different contact point, the bulb lights.

Then ask:

What did you have to do to make it light?
What happens when you lift one wire off?
Can you draw the loop?

Our lesson Can you light a bulb with one wire? is aimed at older children but the activity itself works well with a helper at ages five to seven. The blog post on simple circuit experiments has more detail.

For ages 8 to 10: conductors and insulators

Break the circuit in one place and put different things across the gap: a paper clip, a coin, a rubber band, a plastic spoon, a wooden stick, a piece of foil. If the bulb lights, the thing conducts. If not, it insulates. Sort everything into two groups and look for a pattern. Many (not all) metals conduct and many other materials do not.

Ask them to predict first. Surprises, such as a pencil lead (graphite) conducting, are the best bit. The lesson What lets electricity through? does exactly this.

For ages 10 to 12: series, parallel and why lights go out

Add a second bulb in line with the first. Do both light? Are they dimmer? Then connect them side by side. Is it different? Older children can learn that in a series circuit there is one path, so a break anywhere stops everything. In a parallel circuit, there are several paths, so one bulb can go out while the other stays on. This explains why some old strings of festive lights all fail together. See Why do some string lights all go out at once?.

Common misconceptions

“The battery is full of electricity that gets used up.” The battery pushes charge round the loop and stores energy. It is the energy that runs down, not the charge.
“Electricity needs only one wire.” You need a complete loop, even if the loop is hidden inside a toy or a lamp.
“Bulbs use up the electricity so there is less on the way back.” The same amount of current flows all the way around. The energy is what changes.

You do not need to fix all of these at once. Notice them, and design a test.

Words to build up

Circuit: the loop.
Current: the flow.
Conductor / insulator: lets it through / stops it.
Switch: a gap you can close or open.

Let children make a switch from a paper clip and two pins on a piece of card, and they will soon understand why the light switch on the wall does what it does.

Everyday safety talk

Spend a few minutes talking about what to do around real electricity at home: keep water away from sockets, do not poke things in outlets, ask an adult to unplug appliances, never go near fallen power lines. Short and calm is better than frightening.

Where to go next

The whole simple circuits unit gives a sequence of lessons, and the unit on power up looks at where power comes from for older children. Our kitchen science safety rules apply to any experiment.