- 1. Area vs Perimeter — The Conceptual Distinction
Distinguish area from perimeter; identify the correct units for each; recall and apply the area formula for a rectangle
- 2. Rectilinear Area — Compound Shapes
Calculate the area of compound rectilinear shapes by decomposing into rectangles or completing to a larger rectangle; infer missing side lengths from given information.
- 3. Units of Area — Conversion and Dimensional Reasoning
Identify which units measure area; convert areas between mm², cm² and m²; explain why area conversion factors are the square of length conversion factors
- 4. Area of a Parallelogram — Understanding Perpendicular Height
Identify the base and perpendicular height of a parallelogram in any orientation; distinguish perpendicular height from slant side; verify the formula A = bh on a grid
- 5. Area of a Parallelogram — Full Practice and Inverse Problems
Apply A = bh to parallelograms across all orientations and unit types; solve inverse problems (find a missing dimension given the area); apply the formula in real-world contexts
- 6. Area of a Triangle — Perpendicular Height and the Formula
Identify the base and perpendicular height of a triangle in any orientation, including obtuse triangles where h falls outside; apply A = ½bh accurately with whole numbers, decimals and mixed units
- 7. Area of a Triangle — Reasoning, Composites and Inverse Problems
Explain why triangles with equal base and height always have equal area; build composite shapes (rectangle + triangle); solve inverse problems; find shaded regions by subtraction
- 8. Cumulative Assessment — Lessons 1 to 7
Assess mastery of all GM3 skills from Lessons 1–7: area, perimeter, compound shapes, unit conversion, parallelogram, triangle, composite shapes
- 9. Area of a Trapezium — Formula and Varied Application
Identify the parallel sides a and b and perpendicular height h of a trapezium in any orientation; apply A = ½(a + b)h to calculate areas with whole number and decimal dimensions; convert units where required
- 10. Area of a Trapezium — Real-World Problems and Inverse
Apply A = ½(a+b)h to multi-step real-world problems; solve inverse problems (find a missing parallel side or height given the area); investigate multiple solutions when area is fixed
- 11. Area of Other Quadrilaterals and Polygons — Decomposition
Find the area of rhombuses, kites and arrowheads by decomposing into triangles; apply the principle that any polygon’s area can be found by splitting into triangles; find the area of regular polygons using the apothem method
- 12. Area of a Circle — Formula, Radius and Diameter
Apply A = πr² to find the area of circles given the radius or diameter; halve the diameter before applying the formula; give answers to a specified degree of accuracy (3 s.f. or 1 d.p.); work backwards to find r from a given area
- 13. Circle Composite Shapes — Adding and Subtracting Circle Areas
Find shaded areas by subtracting a circle or semicircle from a polygon; find total areas by adding a circle or semicircle to a polygon; identify the radius from given information about the surrounding shape.
- 14. Problem Solving — Area Mazes, Venn Diagrams, and Investigation
Solve area maze puzzles using the cross-product property; find areas of regions in Venn diagrams; investigate all rectangles with a fixed area and compare their perimeters; generalise findings.
- 15. Final Cumulative Assessment — Lessons 1 to 15
Cumulative assessment covering all GM3 Area skills from Lessons 1–15. Every question tagged [Ln] for targeted revision.
