Mathematics
Intermediate
38 mins
Teacher/Student led
+80 XP
What you need:
IWB/Projector/Large Screen

Area by Counting Square Units

Learn to measure area by counting equal square units on a grid. Discover how to join half-squares, write answers in cm², and see that different shapes can have the same area.

Teacher Class Feed

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    1 - Getting Started ~4 mins

    Illustration for Getting StartedLook at the rectangle on the grid as the square tiles slide in one at a time to fill it. Watch closely: is there a gap or an overlap anywhere?

    Key point

    You already know how to measure the distance around a shape, all along its edge. Today we measure something different: how much flat space is inside it. What could we count to do that?

    2 - Watch and Notice ~9 mins

    Look at the three shapes covered with square-centimetre tiles. Count the squares to find each area. Watch what happens where the last shape's sloped edge cuts squares in half.

    3 - Try It Together ~8 mins

    Today we explore together. When this outline appears on the grid, we count its square units aloud and then write area = ___ cm². We check that no square was missed and none was counted twice, then a few different pupils count it again to be sure.

    Count the square units

    4 - Draw an 8 Cm² Shape in Your Copy ~2 mins

    COPYBOOK MOMENT

    In your maths copy, on the squared page, draw any shape you like that covers exactly 8 whole squares. It does not have to be a rectangle. Then write area = 8 cm² beside it.

    5 - Class Challenge ~7 mins

    We cover and count a few outlines together, taking turns at the board and on our own squared paper:

    1. Cover a 2 by 3 patch and count the units.
    2. Cover an L-shaped patch and count the units.
    3. Cover a triangle with a sloped edge, joining two matching half-squares to make one whole.
    Stretch

    For the stretch: make two different shapes that both have an area of 10 squares.

    Hands-on Task

    6 - What Did We Notice? ~2 mins

    MATHS TALK

    Two shapes cover the same number of squares but look completely different. Do they have the same area? How do you know?

    7 - What's Next ~3 mins

    What we learned today

    • Area is the flat space inside a shape, found by counting equal square units.
    • Every square must be the same size, with no gaps and no overlaps.
    • Two matching half-squares join to make one whole square unit.
    • We write area in square centimetres, using cm².
    Coming up

    Next we look at rectangles more closely and find a quicker way to count their squares: rows times columns, which links straight back to the times tables.

    Pupil practice
    Module 5 · Area, Perimeter and Volume Measures
    Lesson 59 · Area by Counting Square Units
    Download Activity Book page (PDF)
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