How to explain select three-dimensional shapes in 3d shapes to your child: Example question
31 October 2026
Children often see different shapes in maths questions, but it can be tricky to know which ones are three-dimensional. This example helps your child spot the difference between flat (2D) and solid (3D) shapes, using simple objects they might recognise from everyday life.
Worked example
Question: Look at these shapes: a square, a cube, and a circle. Which one is a three-dimensional shape?
Step 1: Look at each shape carefully.
Step 2: Check if the shape has length, width, and height (three dimensions).
Step 3: The square and circle are flat. They only have length and width.
Step 4: The cube has length, width, and height. It is not flat.
The correct answer is the cube.
After looking at this example, your child will be able to tell which shapes have length, width, and height. They will be ready to practise more questions where they select three-dimensional shapes in 3D shapes, building their confidence for the 11+ exam.
