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Subject: Mathematics
Semester: 2
Period: 4
Week: 23
School Name:
Teacher’s Name:
Subject: Mathematics
Grade Level: Grade 1
Date: Week 23
Lesson Duration: 45 minutes
Week & Period: Week 23, Period 4
Topic: Problem Solving
Sub-topic: Addition and Subtraction Word Problems
Learning Objectives
By the end of the lesson, students should be able to:
Solve addition and subtraction word problems involving 2-digit numbers
Identify operation signs from problem statements
Use logical steps to solve problems
Previous Knowledge
Students already know how to add and subtract 2-digit numbers with and without regrouping
Instructional Materials
Mathematics textbook, number lines, counters, flashcards with word problems
Lesson Development – ABC Model
A – Anticipation (Warm-up / Starter)
Time: 5–10 minutes
Teacher narrates a short story problem: “I had 25 sweets. I ate 5. How many are left?” Students answer together.
B – Building Knowledge (Main Lesson Body)
Time: 25–30 minutes
Steps for solving word problems:
- Read the problem carefully.
- Identify what is being asked.
- Identify the numbers and operation needed (+ or –).
- Solve using vertical or horizontal methods.
Example 1: A farmer had 45 goats. He bought 23 more. How many goats in total? (45 + 23 = 68).
Example 2: Musa had 52 oranges. He sold 21. How many oranges are left? (52 – 21 = 31).
Learners’ Activities (Expanded)
Students solve 3 addition and 3 subtraction word problems in pairs.
Students underline key words like “more” or “left.”
Students explain their solutions to the class.
Assessment Checks
Teacher asks students to solve: “There were 34 birds in a tree. 12 flew away. How many are left?”
Notes (Expanded & Detailed)
Word problems test comprehension and application of mathematics in real life. Clue words like “in all” suggest addition, while “remain” suggests subtraction.
C – Consolidation (Conclusion & Assessment)
Time: 5–10 minutes
Summary: Students recall that solving word problems involves reading carefully, identifying the operation, and solving step by step.
Evaluation Method (Expanded)
Exit slip/quiz: Solve one addition and one subtraction word problem. Teacher checks and provides oral corrections.
Assignment (Expanded)
Solve 5 word problems from the textbook.
Follow-up Activity
Students write one word problem of their own and solve it.
Differentiation / Inclusive Strategies
Weaker learners use drawings and number lines. Stronger learners solve mentally and write explanations.
Teacher’s Reflection (After Class)
What worked well? ___________________________________________
What needs improvement? ____________________________________
Students’ engagement level: ☑ High ☑ Medium ☑ Low