How to explain perimeter of figures on grids to your child: Example question
31 October 2026
Understanding how to find the perimeter of figures on grids is a useful skill for many 11+ questions. It helps children see how to measure the distance all the way around a shape, using the grid lines as a guide. This approach is simple and works for rectangles, squares, and more unusual shapes too.
Example question
Find the perimeter of this shape on the grid:
The shape has 4 sides. The top side is 3 units long. The right side is 2 units long. The bottom side is 3 units long. The left side is 2 units long.
Step 1: Count the length of each side along the grid lines.
Step 2: Add all the side lengths together.
3 + 2 + 3 + 2 = 10
Step 3: Write the answer with the unit 'units'.
The perimeter is 10 units.
Key insight: Add the lengths of all the sides around the outside of the shape to find the perimeter.
After seeing this example, your child will recognise that finding the perimeter on a grid means counting each side and adding the totals together. This method can be used for any shape drawn on a grid, and similar questions are ready for your child to practise next.
