Developing Geometry
Overview
Learners will extend their knowledge and understanding of angle facts from Year 7 and solve increasingly complex angle problems. Links are then make to the connected properties of polygons and quadrilaterals. Learners will also learn about further constructions with pairs of compasses.
Following this learners will consolidate their understanding of how to find the area of trapezia from Year 7 and extend this to include circles and common sectors. A key aspect of this half term is for learners to be able to choose and use correct formulae reinforcing shapes the names of shapes and their properties.
Transforming shapes by reflection and understanding line symmetry and rotational symmetry is developed at the end of this half term. Here learners can also revisit and enhance their knowledge of types of triangles and quadrilaterals. Please note: rotation and translation are not introduced at this point to enable students to attain a deeper understanding and avoid mixing up the different concepts.
Building on
Angles in Parallel Lines (Year 7 Summer 1)
Constructing Triangles (Year 7 Summer 1)
Perimeter of shapes (Year 7 Spring 1)
Area of Trapezia & Parallelograms (Year 7 Spring 1)
Rounding (Year 7 Autumn 2)
Plotting linear graphs (Year 8 Autumn 2)
Powerful Knowledge
Derive and use the angle sum in any polygon
Derive and use the angle sum of exterior angles of any polygon
Understand properties of triangles, quadrilaterals and circles
Use compasses to construct bisectors
Derive and apply formulae for area and circumference of a circle
Recognise line symmetry
Reflect shapes in vertical, horizontal and diagonal lines
Describe rotational symmetry
Lesson Resources
Angles in Polygons
Lesson 1 – Interior angles of polygons
Lesson 2 – Exterior angles of polygons
Lesson 3 – Solving polygon problems
Lesson 4 – Constructing polygons
Area and Perimeter of Circles
Lesson 6 – Constructing an angle bisector
Lesson 7 – Constructing a perpendicular bisector
Lesson 8 – Circumference of a circle
Lesson 9 – Circumference problems
Lesson 11 – Area of compound shapes
Lesson 12 – Further area and perimeter problems
Symmetry and Reflection
Lesson 13 – Reflecting shapes on a coordinate grid
Lesson 15 – Rotational symmetry
Updated July 2024