Perimeter and Area

Scheme of work: GCSE Foundation: Year 9: Term 4: Perimeter and Area

Choose and use appropriate standard units to estimate and measure length/height in any direction (m/cm); mass (kg/g); temperature (°C); capacity (litres/ml) to the nearest appropriate
unit, using rulers, scales, thermometers and measuring vessels
compare and order lengths, mass, volume/capacity and record the results using >, < and =
measure, compare, add and subtract: lengths (m/cm/mm); mass (kg/g); volume/capacity (l/ml)

Perimeter is a measure of length around the outside of a shape, whereas area is the space on a surface.
Students should be given the opportunity to derive formulae to calculate the area and perimeter of shapes.
Area is measured in square units.
Demonstrate a triangle as being half a rectangle so students know to use the perpendicular height in their calculation.
Demonstrate a parallelogram as having an equal area to a rectangle.
To calculate the area of composite rectilinear shapes have students break them up in different ways.

Students often confuse area and perimeter.
Students can forget to include correct units when stating an area or perimeter.
When calculating the area of a triangle or parallelogram students tend to use the slanted height rather than the correct perpendicular height.