Measurement and Data
Area by counting squares
Measure the area of a shape on squared paper by counting the squares it covers, including half squares.
Perimeter measures the edge of a shape; area measures the flat space inside it. The simplest way to measure that space is to draw the shape on squared paper and count the squares it covers. No formula is needed and none is used here — the count itself is the area, and it is measured in squares rather than in units of length.
Halves pair up
A shape with slanting edges cuts some squares in half. Those are not thrown away and they are not counted as wholes: two halves make one whole square, so six half squares are worth three. Count the full squares first, then pair up whatever is left.
Worked example
A rectangle on squared paper is 7 squares across and 4 squares down. How many squares does it cover?
The top row holds 7 squares.
The width tells you how many squares fit along a row.
Try it together
Now let us find the area of an L-shape together.
It is made of a rectangle 5 squares by 3 squares with a smaller rectangle 2 squares by 2 squares joined onto its side.
1.How many squares does the 5 by 3 rectangle cover?
Have a play
Three shapes sit on the same grid of squares. Count the squares under each one and compare what you find with how big each shape looks.
Tap any part of the picture.
Have a go
Have a go on your own: a shape covers 16 full squares and 8 half squares. What is its area, in squares?
Hint: Pair the halves up before you add them on.
Ready to practice?
Eight questions on what you have just read. Nothing is timed, and you can play as many times as you like.