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Subject: Mathematics
Semester: 1
Period: 1
Week: 4
School Name:
Teacher’s Name:
Subject: Mathematics
Grade Level: Grade 3
Date: Week 4
Lesson Duration: 45 minutes
Week & Period: Week 4, Period 1
Topic: Sets – Concepts and Applications
Sub-topic: Subsets, Disjoint Sets, Union and Intersection
Learning Objectives
By the end of the lesson, students should be able to:
Identify sets and subsets
Describe disjoint sets, union, and intersection
Apply set concepts using real-life data
Previous Knowledge
Students already know how to group objects by color, size, or type.
Instructional Materials
Mathematics textbook, charts of Venn diagrams, classroom objects.
Lesson Development – ABC Model
A – Anticipation (Warm-up / Starter)
Time: 5–10 minutes
Teacher groups learners into boys and girls and asks what each group represents.
B – Building Knowledge (Main Lesson Body)
Time: 25–30 minutes
Teacher defines a set as a collection of well-defined objects. Example: Set of vowels {a, e, i, o, u}.
Teacher defines a subset as a smaller set inside a bigger set.
Teacher defines disjoint sets as sets with no element in common. Example: Set of even numbers and set of odd numbers.
Teacher defines union (∪) as combining two sets. Example: {1,2,3} ∪ {3,4,5} = {1,2,3,4,5}.
Teacher defines intersection (∩) as common elements in two sets. Example: {2,4,6} ∩ {4,5,6} = {4,6}.
Learners’ Activities (Expanded):
Learners form sets with classroom items.
Learners draw Venn diagrams to show union and intersection.
Learners identify disjoint sets.
Assessment Checks:
What is A ∪ B if A = {1,2,3}, B = {3,4,5}?
What is A ∩ B?
Notes (Expanded & Detailed):
Sets are written inside curly brackets {}. Symbols: union (∪), intersection (∩). Subsets are smaller sets within a set.
C – Consolidation (Conclusion & Assessment)
Time: 5–10 minutes
Summary: Teacher reviews definitions of sets, subsets, disjoint sets, union, and intersection.
Evaluation Method (Expanded):
Exit slip: Draw a Venn diagram showing A = {1,2}, B = {2,3}.
Assignment (Expanded):
Form sets of your family members and show union with your friend’s family set.
Follow-up Activity:
At home, learners group household items into sets and subsets.
Differentiation / Inclusive Strategies
Teacher uses real-life examples for struggling learners.
Teacher’s Reflection (After Class)
What worked well? ___________________________________________
What needs improvement? ____________________________________
Students’ engagement level: ☑ High ☑ Medium ☑ Low