Burglar Alarm for the Three Bears. – Practical Primary Science

Target Audience

Lower Key Stage 2

Sc 4. Physical Processes Key Stage 2 (yr 4)

Children should be taught to:

“ construct a simple electrical circuit, identifying and naming its basic parts, including switches and buzzers
Identify whether or not a lamp will light in a simple series circuit, based on whether or not the lamp is part of a complete loop with a battery”
“recognise some common conductors and insulators and associate metals with being good conductors”

To create problem solving situations to enthuse children and to give their learning a meaningful practical context.
Electricity is a fascinating topic for children to study as it involves direct “first hand” construction activities that can be undertaken very safely but can have dramatic consequences allowing children to let their imagination run wild with what they can design.

Clearly none of this can be undertaken until the children have had the experience of making simple circuits and opportunities to make simple switches, of which the folded card / foil pressure switch is just one.

Shoe boxes again are top of the list,
Pieces of stiff card/ hardboard big enough to provide an area slightly larger than the shoe box when it is laid on its side,
*plastic coated wire, *bulb holders, *bulbs, silver foil, *batteries (1.5volts) *battery holders.

*Schools should have this easily obtainable equipment from their

LEA suppliers

Watch the video clip “Burglar Alarm for the Three Bears” on the website: www.practicalprimaryscience.co.uk
Take a shoe box and carefully slit the lid in two of its corners to create a flap
Lay the shoe box on its side and draw diagonal lines to each corner. Mark the middle and carefully create a slit* in the form of a

cross to allow a bulb holder to be fitted into the hole

Use the lid of the box to form a roof on the box when it is on its side and cut two triangular stiff pieces of card to support the roof
Fix up an electrical circuit using the components mentioned to form a circuit with the two open ends of the circuit attached to a simple pressure switch made with card and silver foil.
Place the shoe box on to the card base. The pressure switch acting as a door mat for entry into the house of the three bears
Decorate the house appropriately (inside of the shoe box)

*Craft knives used by adults only

If sufficient adult help and apparatus is available the class should be split into groups of threes/fours
If only one adult helper is available then one group only will undertake the activity at a time with other children taking part in associated activities such as: retelling the story with their own particular ending

As Goldilocks tries to enter the house of the three bears she stands on the front door mat and the light comes on, thus completing the circuit…….Goldilocks runs away!

Literature has an important role to play here. In the junior department. The making of a circuit to light up / flash the eyes of a model made from cardboard boxes for the Iron Man in Ted Hugh’s classic tale is just one example of how to make electricity exciting for children.
Or a model of an owl with flashing eyes* from the tale of “The owl who was afraid of the dark” by Jill Tomlinson

An egg box provides the perfect setting for two bulb holders sitting

on top of an empty clean baked bean tin covered in feathers