Estimating Area using Grid Paper

The Grid Method

We can estimate the area of simple closed shapes (even curved ones like leaves) using squared paper or graph paper where every square measures $1 \text{ unit} \times 1 \text{ unit}$.

The Rules of Estimation

1. Full Squares: Count full squares as 1 sq unit.
2. Half Squares: Count exact half squares as $\frac{1}{2}$ sq unit.
3. More than Half: If a shape covers more than half of a square, count it as 1 sq unit.
4. Less than Half: If a shape covers less than half of a square, ignore it (count as 0).

Why not use circles?

Squares pack tightly without gaps. Circles leave gaps between them, making it impossible to cover a surface completely to measure area accurately. This is why standard units of area are squares ($m^2$, $cm^2$).