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Subject: Mathematics
Semester: 2
Period: 6
Week: 31
School Name:
Teacher’s Name:
Subject: Mathematics
Grade Level: Grade 3
Date: Week 31
Lesson Duration: 45 minutes
Week & Period: Week 31, Period 6
Topic: Geometry – Basic Figures
Sub-topic: Introduction to Lines, Shapes, Angles, and Vertices
Learning Objectives
By the end of the lesson, students should be able to:
• Classify simple geometric figures: line segments, rays, lines, squares, rectangles, triangles, cones, right angles, and vertex
• Identify and draw different types of angles
• Recognize and name a vertex in shapes
Previous Knowledge
Students already know how to draw straight lines, name simple shapes like circles and squares, and identify sides in objects around them.
Instructional Materials
Mathematics textbook for Grade 3, rulers, protractors, chart papers, sticks, and strings
Lesson Development – ABC Model
A – Anticipation (Warm-up / Starter)
Time: 5–10 minutes
Teacher asks learners to look around the classroom and name shapes they can see (e.g., windows – rectangles, wall corners – right angles, ceiling edges – lines). Teacher then draws a line and a triangle on the board and asks learners: “What do you notice about these figures?”
B – Building Knowledge (Main Lesson Body)
Time: 25–30 minutes
A point shows an exact position. It has no length or width. A line is a straight path extending endlessly in both directions. A line segment is part of a line with two fixed endpoints. A ray has one endpoint and extends endlessly in one direction.
2D figures include square (4 equal sides, 4 right angles), rectangle (opposite sides equal, 4 right angles), and triangle (3 sides, 3 angles).
A vertex is the point where two or more lines meet (plural: vertices).
Angles are formed when two rays meet at a point. Right angle = 90°, acute angle < 90°, obtuse angle > 90° but < 180°.
Example 1: A rectangle has 4 sides, 4 right angles (90°), and 4 vertices.
Example 2: Draw a triangle with sides 4 cm, 5 cm, and 6 cm. Identify the 3 vertices (A, B, C) and the 3 angles.
Learners’ Activities (Expanded):
Learners use rulers to draw lines, line segments, and rays in their books. They form different shapes using sticks and strings, then identify sides, angles, and vertices. Learners label angles on a chart using a protractor.
Assessment Checks:
Teacher asks learners to:
• Draw a square and mark its 4 vertices
• Identify the type of angle formed in a corner of the classroom
• Differentiate between a line and a line segment
Notes (Expanded & Detailed):
Geometry is the study of shapes and their properties. Basic figures include points, lines, angles, and 2D shapes. Every shape has sides, angles, and vertices. Angles are measured in degrees (°). A right angle is a quarter turn, an acute angle is smaller than a right angle, and an obtuse angle is larger than a right angle.
C – Consolidation (Conclusion & Assessment)
Time: 5–10 minutes
Summary: Teacher reviews points, lines, line segments, rays, 2D figures, vertex, and angles.
Evaluation Method (Expanded):
Exit slip/quiz:
Draw and name one line, one ray, and one line segment
Name two shapes that have right angles
Teacher will collect slips and provide oral feedback.
Assignment (Expanded):
Learners will draw one rectangle and one triangle, labeling all vertices and angles.
Follow-up Activity:
In groups, learners will use sticks or straws at home to form different shapes and bring them to class.
Differentiation / Inclusive Strategies
Teacher will provide hands-on activities for slow learners (e.g., using sticks and string). Advanced learners will be challenged to classify angles into acute, obtuse, and right.
Teacher’s Reflection (After Class)
What worked well? ___________________________________________
What needs improvement? ____________________________________
Students’ engagement level: ☑ High ☑ Medium ☑ Low