Area (age 8+)
Measure areas by counting unit squares (square cm, square m, square in, square ft)
What a learner can do afterwards
- Count unit squares to find the area of an L-shaped figure
- Measure the area of a book cover using square-centimetre tiles
- Compare areas of two shapes by counting their unit squares
The lesson
Area is the amount of flat space inside a shape. To measure it exactly, cover the shape with small squares that are all the same size, called unit squares, then count them. If each square is one centimetre wide, you are counting square centimetres. The same idea works for square metres, square inches, and square feet.
Mia draws an L-shaped figure on centimetre paper. She counts the unit squares inside it one part at a time: 5 squares in the tall part and 3 squares in the short part. 5 plus 3 is 8, so the area of her figure is 8 square centimetres.
You can compare two shapes by counting the unit squares inside each one. Whichever shape has more unit squares has the bigger area, even if the shapes look very different.
Sometimes a square is only half inside the shape. Count it as about a half instead of a whole square, then add the halves together for a sensible estimate.
Area is the number of unit squares that fit inside a shape, so count them all and estimate sensibly for any partial squares.
Watch it
Where it sits
Learn first
Where this leads
8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.