Understanding Angles for 11+ Maths: What Parents Need to Know
19 October 2026
Why angles matter in 11+ Maths
Angle questions are a regular feature of the 11+ Maths exam. Children are expected to use angle facts and rules to solve problems, not to measure or estimate by eye.
Types of angles to recognise
Your child should know the difference between acute, right, obtuse, straight, and reflex angles. An acute angle is less than 90°, a right angle is exactly 90°, an obtuse angle is between 90° and 180°, a straight angle is 180°, and a reflex angle is more than 180° but less than 360°.
Essential angle facts
There are five key angle facts for the 11+:
- Angles on a straight line add up to 180°
- Angles around a point add up to 360°
- Angles in a triangle add up to 180°
- Angles in a quadrilateral add up to 360°
- Vertically opposite angles are equal
No measuring, just calculating
Children are not allowed a protractor in the 11+. Diagrams are often not drawn to scale, so answers must be found by calculation, not by guessing or measuring. Encourage your child to trust the numbers given, not the appearance of the diagram.
How parents can help at home
Ask your child to explain which angle rule they are using in each question. Practise identifying angle types and using the five facts above. Remind them to double-check that their answers make sense, especially if a diagram looks misleading.
Key insight: Angle questions in the 11+ are about applying a small set of rules, not measuring or estimating. Focusing on these core facts gives children confidence and accuracy.
Building confidence with angles
Regular practice with labelled diagrams and written questions helps children get used to applying the rules. If your child makes a mistake, talk through which rule they should have used, and try a similar example together.
