An introduction to a simple electrical circuit. The battery pushes the electricity along the wires from the positive terminal, through the bulb and back to the negative terminal. This creates a circuit. To turn out the light, the circuit needs to be broken by adding a switch. It does not matter where the switch goes as the effect is the same. The bulb glows because electricity flows through the filament. When the bulb gets old, the filament breaks and this breaks the circuit.

First broadcast:
9 October 2007

Pupils could be asked what they understand an electric circuit to be and to draw their ideas on whiteboards. The clip could then be shown and compared with pupils' own understanding of it and to amend any misunderstanding. A practical session could then follow through building simple circuits on boards with a switch in. Extension activities could include designing their own lamp in D&T or investigating how to make a water or potato clock. There could also be a link with environmental issues and pupils could monitor electricity consumption in school and at home. A plan could be drawn up with ideas of how to save electricity and not waste it.