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Subject: Mathematics
Semester: 1
Period: 1
Week: 5
School Name:
Teacher’s Name:
Subject: Mathematics
Grade Level: Grade 4
Date: Week 5
Lesson Duration: 45 minutes
Week & Period: Week 5, Period 1
Topic: Subtraction of Whole Numbers
Sub-topic: Using Population Data
Learning Objectives
By the end of the lesson, students should be able to:
Subtract multi-digit numbers with and without borrowing
Interpret decreases in population data using subtraction
Previous Knowledge
Students already know how to subtract numbers up to four digits
Instructional Materials
Mathematics textbook for Grade 4, population data chart, marker board
Lesson Development – ABC Model
A – Anticipation (Warm-up / Starter)
Time: 5–10 minutes
Teacher asks: If a town has 5,240 people and 1,120 people move away, what is the new population?
B – Building Knowledge (Main Lesson Body)
Time: 25–30 minutes
Definition:
Subtraction is the mathematical process of finding the difference between two numbers. It tells us how much is left when one quantity is taken away from another.
We use the minus sign (–) and the answer is called the difference.
Key Vocabulary:
- Minuend – the number you subtract from
- Subtrahend – the number you take away
- Difference – the result
- Regrouping (Borrowing) – taking value from a higher place to subtract when the top digit is smaller than the bottom digit
Examples (Step-by-Step):
Example 1: Without Regrouping
45,620 – 23,410
Step-by-step subtraction:
45,620
– 23,410
22,210
→ All digits in the minuend are greater than or equal to the digits in the subtrahend; no borrowing needed.
Example 2: With Regrouping (Borrowing)
82,530 – 41,245
Step-by-step:
Ones: 0 – 5 → borrow from tens → 10 – 5 = 5
Tens: 2 (became 1) – 4 → borrow → 11 – 4 = 7
Hundreds: 4 (became 3) – 2 = 1
Thousands: 2 – 1 = 1
Ten-thousands: 8 – 4 = 4
Final Answer: **41,285**
Example 3: Real-Life Word Problem (Population Decrease)
A city had 10,000 residents. Due to emigration, 2,430 people left.
10,000 – 2,430 = 7,570 people remaining
Example 4: With Multiple Regrouping
62,410 – 31,245
Step-by-step:
Ones: 0 – 5 → borrow → 10 – 5 = 5
Tens: 1 – 4 → borrow → 11 – 4 = 7
Hundreds: 3 – 2 = 1
Thousands: 2 – 1 = 1
Ten-thousands: 6 – 3 = 3
Final Answer: **31,165**
Why Subtraction is Important:
Subtraction is used to:
- Find how much remains
- Measure decline or decrease (e.g., population, money, resources)
- Solve word problems in real-life settings
- Compare quantities
Common Mistakes to Watch For:
- Not borrowing correctly from the correct place value
- Forgetting to adjust digits after borrowing
- Subtracting larger digit from smaller digit without regrouping
Learners’ Activities (Expanded):
- Group Word Problems – Population Stories:
- Each group is given a city population and a number of people who left due to death or migration.
- Task: Write a subtraction sentence and solve.
- Example:
- City A: 38,270 residents
- 4,580 people moved out
- Students calculate the new population.
- Create Subtraction Stories:
- Students individually write short subtraction word problems using real-life contexts (e.g., school enrollment drop, money spent, number of students who left class).
- Visual Aids – Number Diagrams:
- Draw place value charts.
- Shade or cross out blocks to demonstrate subtraction.
- Helps visualize borrowing.
- Peer Teaching:
- One student explains each step to a partner.
- Peer checks if regrouping was applied correctly.
- Hands-on Activity – “Borrowing Relay” Game:
- Students line up in teams.
- Each member completes one column of subtraction (starting from ones).
- Next student continues with tens, etc.
- Objective: Solve multi-digit subtraction problem as a team.
Assessment Checks:
Oral Questions (Quick Fire):
- What is 62,410 – 31,245?
→ Answer: 31,165 - A town had 50,000 people. 4,230 moved away. What is the population now?
→ Answer: 45,770
Written Exercise:
- Subtract:
75,630 – 28,214 = ________
b. 64,982 – 36,459 = ________
c. 41,500 – 19,234 = ________ - Word Problem:
- A school had 2,365 students. After exams, 479 students transferred out. How many are left?
- Challenge:
- A shop had 87,000 items. They sold 45,789 items in one month.
- How many items remain?
- If 6,890 more are sold next month, what will be the new stock?
- How many were sold in total?
Notes (Expanded & Detailed):
- Subtraction is a reverse process of addition.
- You can check your answer by adding the difference to the subtrahend.
- E.g., 82,530 – 41,245 = 41,285
→ Check: 41,285 + 41,245 = 82,530 ✅ - Borrowing is an essential skill for subtracting multi-digit numbers.
- Helps in accurate calculation when the digit on top is smaller.
- Place value understanding is critical in multi-digit subtraction.
- Helps students line up digits correctly and apply borrowing precisely.
Homework / Practice Activity:
Instructions: Solve the following subtraction problems and word problems. Show all steps.
- 89,450 – 36,780 = __________
- 71,000 – 28,234 = __________
- A town had 24,850 people. 3,946 people left. What is the remaining population?
- A warehouse stored 45,200 bags of rice. If 18,976 bags were sold, how many bags remain?
- BONUS: Create your own subtraction story using population, money, or goods. Write the subtraction sentence and solve it
C – Consolidation (Conclusion & Assessment)
Time: 5–10 minutes
Summary: Students review subtraction with and without borrowing. Teacher highlights real-life applications in population data.
Evaluation Method (Expanded):
Exit slip/quiz: Subtract 73,410 – 52,235.
Assignment (Expanded):
Solve three subtraction word problems from textbook page ___.
Follow-up Activity:
Students create subtraction stories using real-life family or community changes.
Differentiation / Inclusive Strategies
Weaker learners use base-ten blocks for support. Advanced learners solve larger 6-digit subtraction problems.
Teacher’s Reflection (After Class)
What worked well? ___________________________________________
What needs improvement? ____________________________________
Students’ engagement level: ☑ High ☑ Medium ☑ Low