Activity

Discussion

Aim/Facts

1. Blow up a balloon and let it go. Ask some of the children to blow up balloons. Burst a balloon and point out that some of the energy used to blow it up has caused the sound of the bang. Point out that all this is tiring.
Ask how they feel if they are tired and then have a good meal.
Slide 2 and 3
See safety note

Our energy comes from the food we eat.

Food such as sweets have lots of energy in them.

2. Show some mechanical toys, musical instruments, and tools etc
Slide 4
See apparatus list
See safety note

Keep asking what is needed to make them work. Keep saying ‘Yes that needs energy’.

Energy makes things work.

3. Hold up an electric hairdryer (or other household appliance) and ask what they need to do to make it work.
Slide 5
See safety note

Get them to tell you that you need to plug it into the mains.

Lots of things we use around our homes need electricity for them to work.

4. Extra
Ask them to imagine what we would use if we did not have electricity from the mains.
Slide 6

Without electricity our homes would be very different.

5. Explain that electricity is the flow of very, very tiny particles (called electrons).
Slide 7

Tell them that they can play a game where they are the particles. (Explain the word ‘particles’ as meaning ‘tiny things’.)

Electricity is a flow of tiny particles (electrons).

6. Game: Arrange the children in a circle. Place the large bowl containing dry pasta at one side of the circle. The children walk round the circle and as they pass the bowl they pick up a piece of pasta then keep on moving. As they pass a pan, with a thin up-turned lid, they drop the pasta on the lid so a sound is made.
See apparatus list
See safety note

Explain that the circle represents an electrical circuit. The children represent the particles (electrons) and the pasta represents the energy which is collected by the particles from the power-point. The pan represents an electric bell. The energy is used to make the sound.

The electricity carries the energy to where it is needed.

This is very useful.

7. Circuits:
Show the animated circuit in slide 8.

Point out that:
The electrons are all round the circuit before the switch is closed. When the switch is closed the battery is connected across a complete loop of conducting material. Then the electrons move round the circuit as the electricity flows.
(This is explained in the presentation on ‘Electricity’.)

8. Hold up a piece of wire 10 cm long and about 1mm thick. Explain that there are a huge number of electrons in the piece of wire. There are one hundred billion, billion electrons in the wire.
Slide 9
Alternatively use the analogies in the ‘Electricity’ presentation.

Ask them for the biggest number they know.
There could be a guessing game where they are encouraged keep increasing by millions.
Point out that if the same number of small marbles were melted to make a huge marble – it would be bigger than the Earth.
Or if we measured the distance to the nearest star in millimetres we would get about same huge number!

Electrons are very, very, very tiny - far too small for us to be able to see them.

9. Circuits: slide 10
Revise what they know from other activities:

Slide 11
Reinforce:
by using electricity we can make things work just where we want. That the energy flows round wires and is clean – no mess in the house.

Point out that:
The electrons are all round the circuit before the switch is closed. They move round the circuit as the current flows. Then when the switch is opened they are still all round the circuit.

You could use the game in the ‘Electricity’ presentation.

If you want to do something useful – you need energy.

Electricity brings energy to where you need it.

10. Point out that we know why electricity is useful but need to know how it is made.
Slide 12

Batteries or generators make electricity.

11. Lemon battery demonstration:
See apparatus list for details.
Have 4 lemon batteries prepared with a 2p coin and a zinc coated nail in each.
Connect a circuit with one lemon. Then try two lemons. Three lemons should light a red LED dimly. Four will light the LED brightly.
Slide 13

Explain that a battery needs to have an acid and two different metals dipped in it. The lemon juice is acidic, the coin is copper and the nail is covered with zinc. Other combinations work as well.
(Extra- each lemon is a cell. When cells are connected together they are called a battery.)

A chemical reaction occurs which releases energy.

The energy is stored in the battery.

When a battery is connected in a circuit the electrons carry the energy to where it is needed.

12. Ask them to tell you when they use batteries and deduce the advantages and disadvantages of batteries.
Then show slide 14

Batteries are portable and cheap.
They only store small amounts of energy.

13. Generators work because a moving magnet can cause the electrons to move round the circuit.
Slides 15,16,17

Moving a magnet near a wire can generate electricity.

14. Demonstration of a model generator using a magnet.
Take the bung from the tube and show the magnet inside. Point out that there is no battery.
See apparatus list
See safety note on neodymium iron boron magnets

Energy used to move the magnet is carried by electrons to where the energy is needed.

15. Demonstrate a ‘Faraday’ torch. Shake it to show the magnet moving through the coil.
Slide 18
If available show a ‘wind-up’ torch.

Explain that these use new materials which have been developed by scientists and produce very strong magnetic fields.

16. Re-cap
Slide 19

17. Bicycle and lamp
Prop up the bicycle so that the back wheel is off the floor. Then ask a child to pedal.
Slide 20

Ask them why the cycle lamp lights and point out the dynamo. Explain that is works by a magnet moving by a coil of wire.
Explain that if the lamp was a traditional 100 watt lamp bulb, then they might just be able to light it. Even a very strong adult working very hard would only be able to light two lamps.

18. Point out that everyday we use lots of electricity. Much, much more than just two 100 watt lamp bulbs.
This is made by huge generators.

These huge generators need huge amounts of energy to produce the electricity.
There is a lot more to learn about electricity generation.
This will be in Part 2.

Scientists are inventing new ways of generating huge amounts electricity.

• Overview
• Apparatus List
• Safety Notes
• PowerPoint demonstration
• Download, Activities, Apparatus List and Safety Notes as a combined Word document for ease of printing