Home Page

Cotmanhay Junior School

Safe, Happy Learning

Week 8 - 9 Perimeter, area and volume

National curriculum content


  • Recognise that shapes with the same areas can have different perimeters and vice versa
  • Recognise when it is possible to use formulae for area and volume of shapes
  • Calculate the area of parallelograms and triangles
  • Calculate, estimate and compare volume of cubes and cuboids using standard units, including cubic centimetres (cm3 ) and cubic metres (m3), and extending to other units [for example, mm3 and km3 ]


Lesson objectives


  1. Shapes – same area
  2. Area and perimeter
  3. Area of a triangle (1)
  4. Area of a triangle (2)
  5. Area of a triangle (3)
  6. Area of a parallelogram
  7. Recap - What is volume?
  8. Volume – counting cubes
  9. Volume of a cuboid



What we want children to know


  • Relate the area of rectangles to parallelograms and triangles, for example, by dissection, and calculate their areas, understanding and using the formulae (in words or symbols) to do this
  • Find and draw rectilinear shapes that have the same area
  • Extend their knowledge of working out the area of a right-angled triangle to work out the area of any triangle
  • Understand that volume is the amount of solid space something takes up
  • Make the link between counting cubes and the formula (𝑙 × 𝑤 × ℎ) for calculating the volume of cuboids


What skills we want children to develop

Use knowledge to solve reasoning and problem solving questions such as:


Top Tips

  • Put these amounts in order starting with the largest.

100 cm3

1000000 mm3


Explain your thinking


Always, sometimes, never


  • If the area of a rectangle is odd then all of the lengths are odd.


Other possibilities


  • A cuboid has a volume between 200 and 250 cm cubed. Each edge is at least 4cm long. List four possibilities for the dimensions of the cuboid.


Vocabulary/Mathematical Talk


  • What do we need to know in order to work out the area of a shape?
  • Why is it useful to know your times-tables when calculating area?
  • What is the difference between the area and perimeter of a shape?
  • What does estimate mean?
  • What is the formula for working out the area of a rectangle or square?
  • What do we mean by perpendicular height?
  • Describe a parallelogram.
  • How is capacity different to volume?
  • What is the same and what’s different between area and volume?
  •  Can you identify the length, width and height of a cuboid?