Children can feel inspired, motivated and spend more time engaged on task when the problems posed involve them searching for a purposeful outcome, particularly when some-one is asking for their advice! The sensor activity on page 16 of our publication ‘Generating Electricity’ (which can be found at http://www.ciec.org.uk/resources/generating-electricity.html) provides this kind of context and would be a useful challenge to give children during ‘Tomorrow’s Engineers Week’ (6th -10th November) while covering KS2 objectives for electricity.
After receiving a letter from ‘Electricaid’ children work collaboratively to design and build a mini working model of a well which includes some kind of sensor to warn when the water has reached a desired level. Each group is given a large beaker (1000ml) to represent their well, one 1.5V cell and the rest is up to them!
The most innovative designs are achieved when children are provided with a selection of basic circuit equipment as well as lots of everyday conducting and insulating materials to choose from - paper clips, drawing pins, split pins, coins, corks, cotton reels, tin foil, bottle tops, glue, blu-tac, sellotape, card, plastic tubes and plastic sheets (A4 overhead projector transparencies are ideal) plus anything else that the children think they will need.
Children are encouraged to discuss and swap ideas not just at the planning stage but throughout this activity, jotting and amending notes and annotated drawings on whiteboards and listing the types of equipment they may need to start with and then to modify and improve their designs. Giving children space to make mistakes as they design and evaluate their designs through a process of trial and error helps children to develop a deep understanding of what they are doing as well as fostering real pride in their achievements.
It can be valuable not to show children the diagram of a successful design which is provided in the resource until after they have made their own sensors. When they do this teachers are amazed at the variety of ideas and at the ingenuity of children. Most models have some kind of floating conductor (say a ‘raft’ of corks covered in tin foil) placed in the bottom of the well. When water is added and the level rises, this floats up to touch a carefully positioned contact point near the top of the well which is then connected to a simple circuit built safely away from the water.
|Close up of a working sensor|
We would love to see your children’s designs; you can tweet them to @ciecyork for a chance to win a hard copy of some of our resources!