Lesson Plan

• Identify and classify angle types and apply angle‑sum properties in triangles.
• Use parallel‑line angle relationships to determine unknown angles.
• Calculate interior and exterior angle sums of polygons and apply regular‑polygon formulas.
• Apply circle definitions and theorems (central, inscribed, tangent‑chord) to solve geometry problems.
• Perform basic constructions (perpendicular bisector, parallel line, regular hexagon) with ruler and compass.

• Whiteboard and markers
• Projector with geometry slides
• Ruler (unmarked) and compass for each student
• Geometry worksheet with practice problems
• Pre‑drawn diagrams of angles, parallel lines, polygons, and circles
• Protractor (optional for angle measurement)

Begin with a quick visual puzzle showing intersecting lines and a circle, asking students to name the types of angles they see. Review prior knowledge of angle classification and the triangle‑sum rule. Explain that today they will extend this understanding to parallel lines, polygons, circles, and simple constructions, with success measured by accurate calculations and completed constructions.

1. Do‑now (5') – Identify angle types and calculate a missing triangle angle on a short worksheet.
2. Mini‑lecture (10') – Review angle types, triangle sum, and introduce parallel‑line angle relationships with projector diagrams.
3. Guided practice (12') – Solve examples using corresponding, alternate interior, and consecutive interior angle properties; teacher checks understanding.
4. Polygon & circle concepts (10') – Demonstrate formulas for interior/exterior angles of polygons and circle measurements; students complete quick calculations.
5. Construction activity (15') – Students construct a perpendicular bisector, a parallel line, and a regular hexagon using ruler and compass; peer‑check accuracy.
6. Exit ticket (3') – Answer three rapid‑fire questions covering each topic to assess mastery.

Summarise how the angle relationships, polygon formulas, and circle theorems connect to real‑world geometry. Collect exit tickets and remind students to complete the worksheet homework, which includes additional construction and problem‑solving tasks. Encourage them to review the checklist before the next quiz.