Engineering & design · Grades 5–10
Design briefs, criteria and constraints
Define success before choosing a solution.
Learn the idea
Brief
A design brief names the problem, users and intended function.
Criteria
Criteria describe desired performance.
Constraints
Constraints are limits such as size, budget, time and safety.
Iteration
Testing and revision improve a design when evidence is used.
Worked examples
Which is a design constraint?
A constraint limits allowable solutions.
The model must fit inside a 20 cm box.
Which is a performance criterion?
A criterion describes how well the solution should function.
Hold a specified model load without collapsing.
Check your understanding
A model uses pieces costing 12, 8 and 15 units. Find total stated cost.
Why should the intended users be included in the brief?
What should follow a failed prototype test?
- Analyze the failure and revise relevant features.
- Assume all future designs fail.
- Hide the result.
Answers and marking notes
Answers and marking notes
- 35
12 + 8 + 15 = 35.
- Their tasks, abilities and context affect requirements.
Design should solve a defined user problem.
- Analyze the failure and revise relevant features.
Failure data can guide improvement.
Independent educational review required. Grade bands are approximate; these are not officially aligned curricula.