Did you know that a line which looks longest on a Maths worksheet may not represent the largest stated length? For Bukit Timah families, “not drawn to scale” means the picture’s apparent sizes are not a reliable way to determine measurements. Use the given labels, conditions and valid mathematical relationships.
Ask your child to distinguish what is stated from what merely looks true. A right-angle symbol supplies information; a corner that looks square without supporting information does not establish a right angle. Preserve the first interpretation so the tutor can see which visual assumption entered the solution.
Follow the task instructions. If a question explicitly asks for measurement or supplies a scale for that purpose, use the permitted method. Otherwise, bring the labelled diagram and the child’s reasoning to tuition and ask which relationship justifies the answer.
Find your next step
Choose the part closest to your child’s work and try one manageable learning check.
SECTION 1 OF 5
Separate labels from appearance
Read every stated length, angle and condition. Identify any conventional markings, such as equal-side marks or a right-angle symbol, within the student’s taught scope. Ask which facts they communicate.
Do not infer equality, parallelism or a midpoint solely because the picture looks balanced. A helpful diagram shows relationships, but an unscaled drawing need not preserve exact visual proportions.
SECTION 2 OF 5
Use a simple angle example
Suppose the problem states that the angles of a triangle are 40°, 60° and an unknown angle. Their sum is 180°, so the unknown angle is 80°. The drawing’s appearance does not change that calculation.
Ask the child to identify the fact licensing the method: it is a triangle, with the given angle values. A protractor reading from an unscaled sketch would not replace that reasoning.
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SECTION 3 OF 5
Check what has actually been given
If a solution assumes two sides are equal, ask where that information appears. It may be stated in the text, marked on the diagram or established by earlier reasoning. If none applies, the assumption needs review.
This can also reveal a copying or question-reading problem. The child may have overlooked a mark or transferred a label to the wrong segment. Preserve the original diagram rather than redrawing away the uncertainty.
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SECTION 4 OF 5
Follow genuine measurement instructions
Some learning tasks are specifically about drawing or measuring. Others provide a scale diagram for a stated purpose. Read those instructions and use the appropriate tools.
The rule is not “never measure a diagram”. It is “use measurement only where the task supports it”. Ask the tutor to contrast a measurement task with a reasoning task so the difference becomes clear.
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SECTION 5 OF 5
Practise a different-looking sketch
After teaching, use a suitable problem whose layout looks different but preserves the relevant stated relationships. Ask the child to name the given facts before solving. Note whether an unsupported visual assumption returns.
eduKateSG’s Mathematics teaching guide describes clear explanation and inspection of workings within 3-pax tutorials. Bring the diagram, assumed fact and first solution to consultation. The next step is to make the reasoning visible, not merely produce a neater drawing.
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Continue with the closest question
- Choose a useful diagram
- Read graph scales accurately
- Bukit Timah tuition decision guide
- Bukit Timah tuition hub
- eduKateSG’s 3-pax Mathematics teaching guide
Sources and course checks
Reviewed 10 October 2026. The examples are original teaching illustrations, and the home routines are suggestions to discuss with the teacher or tutor. Match practice to actual school coverage, task instructions and the relevant subject and examination year.
Arrange a parent–student consultation after the starting position is clear. Bring the task, first attempt and the point where help was needed.