Know that perimeter is measured in units of length and can be found by counting or measuring units | Maths

Starter quiz

Which of these shows the correct way to measure the line?
Which of these shows the perimeter of the triangle?
Which of these shapes has a different perimeter to the other two?
Select all of the statements that are true of this number shape.
- It has a perimeter. ✓
- Its outline forms a regular shape.
- It has squares inside it. ✓
Is it possible for two different rectangles to have the same perimeter?
- Yes, but it depends on the distance around them. ✓
- Yes, because all rectangles have the same perimeter.
- No. If they are two different rectangles they must have a different perimeter.
What is true of this pair of 2D shapes?
- They have the same perimeter. ✓
- They have different perimeters.
- It is impossible to say which one has a bigger perimeter.

This number shape is made of smaller squares. Complete the sentence. This shape has a perimeter of ______ units.
- '8' ✓
Equal-sized matchsticks have been used to find the approximate perimeter of this square. The square has a perimeter of around ______ units.
- '8' ✓
How can you find the perimeter of this shape?
- Count all the surrounding squares.
- Count the squares inside the shape.
- Count the units around the outside of the shape. ✓
What is the perimeter of this shape?______ units.
- '12' ✓
What is the perimeter of this shape?______ units.
- '14' ✓
Lucas says the perimeter of the shape is 10 units. What mistake might he have made?
- Not counting one of the sides of the shape. ✓
- Counting the squares inside the shape.
- Counting one of the sides twice.

Loading worksheet ...

Loading presentation ...

Pupils may count a side twice, or miss a side, if they do not remember where their starting point was on the shape when counting the perimeter.

Encourage pupils to mark a starting point, or use dots to mark the units they have counted.