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Subject: Mathematics
Semester: 2
Period: 6
Week: 32
School Name:
Teacher’s Name:
Subject: Mathematics
Grade Level: Grade 3
Date: Week 32
Lesson Duration: 45 minutes
Week & Period: Week 32, Period 6
Topic: Geometry – Angles
Sub-topic: Types and Measurement of Angles
Learning Objectives
By the end of the lesson, students should be able to:
• Identify various types of angles
• Measure and construct angles using a protractor
• Name angles correctly in degrees (°)
Previous Knowledge
Students already know how to identify right angles from previous lessons.
Instructional Materials
Mathematics textbook for Grade 3, protractors, rulers, charts
Lesson Development – ABC Model
A – Anticipation (Warm-up / Starter)
Time: 5–10 minutes
Teacher shows classroom objects (door corner, open book, wall clock at 3 o’clock) and asks: “What angle do you see here?” Learners guess whether it is small (acute), large (obtuse), or a right angle.
B – Building Knowledge (Main Lesson Body)
Time: 25–30 minutes
Types of angles:
• Acute angle < 90°
• Right angle = 90°
• Obtuse angle > 90° but < 180°
• Straight angle = 180°
• Reflex angle > 180° but < 360°
Angles are measured in degrees using a protractor. To measure:
Step 1 – Place the center of the protractor on the vertex.
Step 2 – Align one side of the angle with the baseline.
Step 3 – Read the measure where the other side crosses the number scale.
Example 1: Draw a line, place another line at 60°. That is an acute angle.
Example 2: Measure and construct 120°. That is an obtuse angle.
Learners’ Activities (Expanded):
Learners use protractors to draw and measure different angles in their exercise books. Learners participate in an “angle scavenger hunt,” identifying angles from classroom furniture and labeling them.
Assessment Checks:
Teacher asks learners to:
• Measure the angle of a book opened wide
• Draw and name one acute and one obtuse angle
Notes (Expanded & Detailed):
Angles are everywhere in real life. Acute angles are sharp, right angles are square, obtuse angles are wide, straight angles form a straight line, and reflex angles bend backwards. Angles are always measured in degrees (°).
C – Consolidation (Conclusion & Assessment)
Time: 5–10 minutes
Summary: Teacher revises all angle types and demonstrates how to measure them with a protractor.
Evaluation Method (Expanded):
Exit slip/quiz:
Draw one right angle and label it 90°
Draw an angle and measure it using a protractor
Assignment (Expanded):
Measure 3 corners of objects at home and write down their type of angle.
Follow-up Activity:
Learners create a mini chart of 5 angle types and decorate them.
Differentiation / Inclusive Strategies
Learners struggling to measure can use pre-drawn angles. Advanced learners construct reflex angles.
Teacher’s Reflection (After Class)
What worked well? ___________________________________________
What needs improvement? ____________________________________
Students’ engagement level: ☑ High ☑ Medium ☑ Low