Understanding Area
Understand that a unit square has one square unit of area and that the area of a plane figure is the number of unit squares that cover it without gaps or overlaps
What a learner can do afterwards
- Identify a unit square and state its area is 1 square unit
- Explain why a figure covered by 12 unit squares has area 12 square units
- Distinguish between area and perimeter as different measurements
1 · Read
Area tells you how much flat space a shape covers. To measure it, we use unit squares: small squares that are all the same size. One unit square has an area of exactly 1 square unit. Perimeter is different: it measures the distance around the outside edge.
Sam covers a rectangle with unit squares. He counts 3 rows, and each row has 4 squares. That is 12 squares in total, so the rectangle's area is 12 square units.
Area is not the same as perimeter. Area counts the unit squares that cover the inside of a shape. Perimeter measures the distance around the outside edge.
Area is the number of unit squares, each worth 1 square unit, that cover a shape with no gaps or overlaps.
More to read
Key ideas: solve historical math problems involving area
Long ago, the Babylonians needed area to split fields and plan buildings. They covered land with squares and counted. That trick still works. Cover any flat shape with unit squares, leaving no gaps. Count the squares. The count is the area. A field covered by 12 squares has area 12 square units. Big fields need big squares, like square metres. Small jobs need small squares, like square centimetres. Pick a square size, cover, and count.
Plane figures FAQ
Area is the amount of space that a flat shape covers. We measure area in square units, like square inches, square centimetres, or square tiles. Knowing area tells you how much paint covers a wall or how much cloth makes a quilt. Perimeter is a different job: it measures the edge, not the fill. A shape can have area 24 and perimeter 24 at the same time, yet the two numbers mean different things.
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2 · Watch
En anglais3 · Play
Fill squares and count the space your shape covers.
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Where it sits
Learn first
Nothing; this is a starting point.
Optional connections
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Where this leads
14 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.