Why do designers build rough models before making the final product, and what can a model tell you?
Make models and prototypes from quick materials to test ideas in three dimensions and inform the final design
A practical answer to the N(A)-Level D&T outcome on modelling and prototyping. Why models are made, suitable quick materials such as card and foam, what tests a model can run, and how results feed back into the design.
Reviewed by: AI editorial process; not yet individually human-reviewed
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What this dot point is asking
SEAB wants you to make models and prototypes from quick, cheap materials to test your ideas in three dimensions before making the final product. A drawing only shows a flat view; a model lets you check size, shape, stability and how something feels in the hand. The skill is choosing what to test and feeding the results back into the design.
The answer
Why model before making
A sketch can hide problems that only appear in three dimensions, such as a stand that tips or a handle that is too small to hold. Making a quick model finds these problems early and cheaply, before you spend time and material on the final product. It is far cheaper to change a card model than to remake a finished item.
Models and prototypes
The two words overlap, but there is a useful difference:
- A model (or mock-up) is a quick, rough version made to test one thing, such as a shape, a size, or a layout. It is often made from card or foam.
- A prototype is a fuller, working version, closer to the real product, made to test how the whole thing works together.
You often make a model first, then a prototype once the idea is more settled.
Quick materials
Good modelling materials are cheap, fast to work and easy to change:
- Card and cardboard for shapes, layouts and boxes.
- Foam board for stronger 3D forms.
- Modelling foam or clay for rounded shapes a user will hold.
- Scrap material for testing a real fixing or joint.
Using the results
A model is only useful if you act on what it shows. Each test result becomes a change: a tipping model leads to a wider base; an uncomfortable handle leads to a thicker grip. Record the test, the result and the change in your journal so the development is clear.
Examples in context
Example 1. A card model of a desk tidy. Before cutting wood, a student folds a card tidy to check the compartments hold real pens and the footprint fits the desk. A pocket is too small, so it is enlarged on the card first, saving a remake in wood.
Example 2. A grip prototype. A student shapes modelling foam into a tool handle and asks users to hold it. The feedback that it is too thin leads to a thicker grip in the final design, something a drawing could not have revealed.
Try this
Q1. Name two quick materials suitable for making a model. [2 marks]
- Cue. Any two of card, cardboard, foam board, modelling foam or clay.
Q2. State the main difference between a model and a prototype. [2 marks]
- Cue. A model is a rough version testing one feature; a prototype is a fuller working version of the whole product.
Q3. Explain why making a model early saves time and material. [3 marks]
- Cue. Because it reveals problems in three dimensions while they are cheap and quick to fix, before time and the final material are spent on a flawed design.
Exam-style practice questions
Practice questions written in the style of SEAB exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.
Original6 marksA student is designing a phone stand and decides to make a model before the final version. Suggest a suitable quick material for the model, describe two things the model could test, and explain how the results would help the design.Show worked answer →
Suitable material: card or foam board, because it is cheap, quick to cut and easy to change.
Two tests: (1) the viewing angle, by checking whether the phone is comfortable to look at; (2) the stability, by checking whether the stand tips when the phone is tapped.
How results help: if the angle is too steep, the student changes it before making the final stand; if it tips, the base is widened. So the model finds problems early and cheaply, before time and material are spent on the final version.
What markers reward: a sensible quick material with a reason, two clear things to test, and the key point that the model reveals problems early so they can be fixed cheaply before the final make.
Original4 marksExplain the difference between a model and a prototype, and why both are useful in designing.Show worked answer →
A model is usually a quick, rough version made to test one part of an idea, such as a shape or size, often from card or foam. A prototype is a fuller working version, closer to the real product, made to test how the whole thing works together. Both are useful because they let you find and fix problems in three dimensions before committing to the final product.
What markers reward: a model as a rough test of a part or shape, a prototype as a fuller working version of the whole, and the shared benefit that both test ideas in 3D and catch problems early.
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