Circle Theorems: Angles in a Semi-Circle – Complete Lesson

This is a complete lesson on angles in a semi-circle that will teach students to prove and use the rule that the angle in a semi-circle is a right angle. The lesson is designed with the new GCSE specification in mind.

Lesson Objectives

  • To be able to prove that an angle in a semi-circle is a right angle.
  • To use the fact that a angle in a semi-circle is 90 degrees to solve problems.

Who is this Lesson For?

This pack is designed for GCSE higher tier students. It could also be used with high ability Key Stage 3 students.

What is Included?

Included in this download are the following:

  • Full lesson plan for the ‘Angles in a Semi-Circle’ lesson, including introduction, teaching content, individual activities, plenary and suggested support and extension activities
  • Angles in a Semi-Circle Demonstration
  • Angles in a Semi-Circle Example
  • Angles in a Semi-Circle Example 2
  • Mini-Plenary
  • Student Worksheet on Angles in a Semi-Circle
  • Vote With Your Feet
  • Circle Theorems Fact Sheet
  • Complete Solutions to all Questions

Lesson Progression

This is the first lesson in the Circle Theorems unit of work (the unit is also available as a pack including homework activities and a unit assessment).

The other lessons in the unit are: