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Subject: Mathematics
Semester: 1
Period: 1
Week: 4
School Name:
Teacher’s Name:
Subject: Mathematics
Grade Level: Grade 4
Date: Week 4
Lesson Duration: 45 minutes
Week & Period: Week 4, Period 1
Topic: Addition of Whole Numbers
Sub-topic: Using Population Data
Learning Objectives
By the end of the lesson, students should be able to:
Add multi-digit whole numbers with and without regrouping
Solve addition problems using population data
Previous Knowledge
Students already know how to add numbers up to four digits
Instructional Materials
Mathematics textbook for Grade 4, population data charts, marker board
Lesson Development – ABC Model
A – Anticipation (Warm-up / Starter)
Time: 5–10 minutes
Teacher asks: If one village has 2,430 people and another has 3,215 people, what is the total?
B – Building Knowledge (Main Lesson Body)
Time: 25–30 minutes
Definition:
Addition is the mathematical process of combining two or more numbers to find their total or sum.
In addition, the plus sign (+) is used, and the answer is called the sum.
Key Concepts:
- Place Value Columns: Ones, Tens, Hundreds, Thousands, Ten Thousands, Hundred Thousands
- Regrouping (Carrying):
When the sum in one column is 10 or more, we regroup (carry) the extra value to the next column on the left.
Why Addition is Important:
- Used in real-life situations:
- Population growth
- Financial accounting (e.g., savings or income)
- School enrollment
- Inventory in businesses
- Data analysis and reports
Step-by-Step Examples (With Regrouping):
Example 1: Without Regrouping
42,315
+27,240
= 69,555
→ Add column by column, no place exceeds 9, so no regrouping is needed.
Example 2: With Regrouping
23,476
+15,739
= ?
Step-by-step:
Thousands | Hundreds | Tens | Ones
3 + 7 = 10 → Write 0, carry 1
4 + 3 + 1 = 8
7 + 5 = 12 → Write 2, carry 1
3 + 5 + 1 = 9
2 + 1 = 3
Final Answer: **39,215**
Example 3: Real-Life Application – Population Growth
A town had 24,350 people. Then 5,260 people moved in.
24,350
+ 5,260
= 29,610
→ The new population is 29,610
Example 4: 5-digit Addition with Regrouping
34,215
+56,321
= ?
Step-by-step:
34,215
+ 56,321
90,536
(Perform column-by-column addition and regroup where necessary.)
Learners’ Activities (Expanded):
- Pair Work – Word Problems:
- Each pair receives 3 real-life population scenarios.
- Example:
- Kakata: 45,672 residents
- 2,834 people migrate in
- Students calculate total population.
- Group Work – Town Populations Table:
- Students in groups are given fictional data of 5 towns.
- Task: Add population of all towns and write total in a table.
- Example:
- Town A: 12,345
- Town B: 18,902
- Town C: 9,670
- Town D: 15,034
- Town E: 21,459
- TOTAL: (Students add these)
- Visual Learning – Bar Graph Creation:
- Based on their totals from group work, students create bar graphs showing each town’s population.
- Use colored pencils to distinguish towns.
- Hands-on Practice – Regrouping Drill:
- Use base-10 blocks or place value charts.
- Teacher provides numbers with 3–5 digits.
- Students solve problems while visualizing how values move between place value columns.
- “Sum It Up” Game (Competition Style):
- Each team is given a set of flashcards with large numbers.
- One member draws two cards and adds the numbers.
- Teams compete for accuracy and speed.
Assessment Checks:
Oral Questions (Quick Check):
- Add 34,215 and 56,321
→ Answer: 90,536 - A town had 24,350 people and 5,260 moved in. What’s the new population?
→ Answer: 29,610 - Add: 78,945 + 14,236
→ Answer: 93,181
Written Exercise (On Board or in Workbook):
- Add the following:
- 17,425 + 23,621 = __________
b. 98,120 + 3,896 = __________
c. 35,675 + 49,218 = __________
Challenge Word Problem:
- "Zorzor has 14,560 people. 6,245 people moved in from nearby villages. Later, 1,450 more people were born. What is the total population now?"
→ Step 1: 14,560 + 6,245 = 20,805
→ Step 2: 20,805 + 1,450 = 22,255
Notes (Expanded & Detailed):
- Addition is a cumulative process, meaning the order of numbers does not affect the result.
(23,400 + 15,610 = 15,610 + 23,400) - Regrouping is important for accurate addition when any column adds up to 10 or more.
- Place value awareness helps students align numbers correctly during vertical addition.
- Use real-world contexts (like population, money, or scores) to make the lesson more relevant.
Homework / Practice Activity:
Instructions: Add the following and show all your work.
- 12,345 + 16,209 = __________
- 74,318 + 5,962 = __________
- A school has 2,569 students. 437 more enrolled this year. How many students now?
- Add:
- Kakata: 23,145
- Bong Mine: 17,394
- Gbarnga: 25,670
- What is the total population?
Bonus Task:
Create your own 2-sentence word problem involving addition of population. Solve it.
C – Consolidation (Conclusion & Assessment)
Time: 5–10 minutes
Summary: Students review addition steps with regrouping and without regrouping. Teacher reinforces applications to population data.
Evaluation Method (Expanded):
Exit slip/quiz: Add 45,210 and 32,405.
Assignment (Expanded):
Solve three addition word problems from textbook page ___.
Follow-up Activity:
Students interview parents about family size changes and add totals.
Differentiation / Inclusive Strategies
Weaker learners use place value charts. Stronger learners solve 3-number addition problems.
Teacher’s Reflection (After Class)
What worked well? ___________________________________________
What needs improvement? ____________________________________
Students’ engagement level: ☑ High ☑ Medium ☑ Low