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COLOURING PLAYDOUGH
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Objectives
- To learn how to investigate and improve
the method for making coloured playdough in order to produce the
most even colour.
- To use industrial style research and
development techniques.
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Curriculum links
English National Curriculum:
Design & Technology: 1a, 2a, 3a, 3c.
| Gateway story
The intention of this gateway, and the activity, is to model or
copy the colouring of materials such as plastics.
Gateway elements
- Playdough chameleon, being studied by the cartoon
chameleon
- Coloured plastic pellets
- Swatch of coloured plastics.
Plastic pellets: Before plastics are moulded, they are often
produced in the form of pellets. (They can also be in in the form
of a 'resin' or powder.) The required colour is added to the material
before the pellets are made, and therefore before moulding.
Plastics swatch: This swatch is used to show customers of
the plastics makers what range of colours is available for the final
products. This is similar to the use of paint colour swatches in
DIY stores.
Gateway discussion
Whilst looking at the gateway, ask the children some of the following
questions:
- Apart from the playdough, what else has had
colour added?
- When do you think the colour has been added? Why?
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Approximate time required:
2½ hours
Resources needed
Hob or other suitable heat source
Plastic sheet/cloth
Apron for each child
Per group:
Playdough recipe
Record sheet
Mixing bowl per group
A cup to use as a measure
Pipette or measuring spoon
Saucepan
Wooden mixing spoon
Cup plain flour
2 tsp cream of tartar
1/3 cup salt
1 tbs cooking oil
Cup cold water
10 ml food colouring (red or blue)
Suggested organisation
Whole class introduction then groups of 3- 4 children
Carrying out the activity
The children can be asked to think about the
benefits to a playdough company of different mixing methods, for example:
- If adding the colour after the cooking works
well, the factory could produce large amounts of plain playdough to
be divided up and given different colours at the end of the process.
Would this be a good idea?
Each group can be responsible for trying a different
mixing method.
This should be a fair test, as in an industrial research laboratory, otherwise
comparisons cannot be made nor recipes repeated in full scale production.
Therefore, the class have to agree on what they want to keep the same,
e.g. the chosen colour and the amount used, number of stirs, kneading
time, etc.
Tell the class that the process and the measurements
would be meticulous under laboratory conditions, as a company's reputation
and profits rely on detail and accuracy. Therefore, the children need
to replicate this attention to detail even if it means working more slowly.
Each group should plan and record exactly what they are doing so that
their results can be compared with the others'. The record
sheet can be used for this purpose or children can design their
own.
If they happen to produce the best result then their method must be precise
enough for anyone else to repeat it in future.
Here are some typical test results that you
might expect:
| Batch |
Method |
Results |
| 1 |
All ingredients put into pan together at
once, mixed, then stirred over heat until thick. |
Colour reasonably even. |
| 2 |
Playdough made up without colour;
colour added at the end of the process. |
Colour uneven and streaky. |
| 3 |
Colour mixed with other liquids then added
to dry ingredients before heating.
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Colour very even. |
| 4 |
Colour added to dry ingredients first,
then liquids added before heating.
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Overall blue colour with dark speckles
of colour. |
Plenary
The resulting samples are displayed with each
group's record sheet. The samples are then examined by all the 'laboratory
scientists' together, to make an overall judgement on the best idea method.
Extensions / links
Design & Technology
The children can be given the task of producing
a range of coloured playdoughs for younger children in the school or nursery.
They use the best method from the main activity and could invent their
own colour recipes. These could be carefully measured, tested and recorded,
as previously. When complete the children could invent names for the different
colours they have produced, e.g. Bubblegum Pink, Tiger Yellow, Beluga
Blue, etc.
ICT
All the recipes can be collected and made into
a booklet.
English / Literacy
The children could produce marketing leaflets,
booklets or posters advertising their recipes. They could include some
of the following:
- Clear instructions on how to make playdough.
- A range of ideas for using playdough.
- Information: it is a cheaper alternative
to buying more ready-made products.
- Information: the ingredients are readily
available at home.
- Information: the ingredients are safe for
young children.
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