3.9 Similar Shapes GCSE PowerPoint Lesson

This 25-slide lesson introduces similar shapes, focusing on identifying and reasoning about shapes that have the same angles and proportional sides. Students will explore how to recognise and prove similarity in triangles, including using angle facts linked to parallel lines. Through diagrams and problem-solving tasks, students will understand how scale factor relates to similarity and apply it to find missing lengths in simple geometric contexts.

 Note this is a foundation lesson. See higher lessons for congruent triangle proofs.

The lesson includes:

• Clear, guided examples

• Discussion opportunities from Think, Pair, Share

• Mini whiteboard section to check understanding and clarify misconceptions

• One structured task to practise key skills

• Challenge activity to extend and deepen learning

Perfect for engaging learners while reinforcing essential geometry concepts.