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Subject: Mathematics
Semester: 1
Period: 2
Week: 8
School Name:
Teacher’s Name:
Subject: Mathematics
Grade Level: Grade 4
Date: Week 8
Lesson Duration: 45 minutes
Week & Period: Week 8, Period 2
Topic: Multiplication
Sub-topic: Multiplying Multiples of 10s, 100s, and 1000s
Learning Objectives
By the end of the lesson, students should be able to:
Multiply whole numbers by 10, 100, and 1000
Recognize patterns in zeros when multiplying
Apply multiplication of 10s, 100s, and 1000s to real-life problems
Previous Knowledge
Students already know basic multiplication facts and place value of numbers
Instructional Materials
Mathematics textbook, place value chart, flashcards, counters
Lesson Development – ABC Model
A – Anticipation (Warm-up / Starter)
Time: 5–10 minutes
Teacher reviews basic multiplication facts. Example: 3 × 5 = 15
Learners predict what will happen when multiplying by 10. Example: 3 × 10 = ?
B – Building Knowledge (Main Lesson Body)
Time: 25–30 minutes
Definition and Explanation (Expanded & Detailed)
When we multiply a number by 10, 100, or 1,000, we are increasing its value by shifting its digits to the left on a place value chart.
This is because we are multiplying by powers of 10.
- Multiplying by 10 shifts digits 1 place left
- Multiplying by 100 shifts digits 2 places left
- Multiplying by 1,000 shifts digits 3 places left
This method makes multiplication with these values faster and easier.
Examples (More & Varied)
Basic Examples:
- 6 × 10 = 60
- 23 × 100 = 2,300
- 45 × 1,000 = 45,000
Expanded Worked Examples:
- 72 × 10 = 720
- 56 × 100 = 5,600
- 12 × 1,000 = 12,000
- 109 × 10 = 1,090
- 87 × 100 = 8,700
- 306 × 1,000 = 306,000
- 21 × 100 = 2,100
- 1 × 10 = 10
- 7 × 1000 = 7,000
Real-Life Application Examples
- A school has 120 students in one class. How many students in 10 classes?
→ 120 × 10 = 1,200 students - A factory produces 250 items per day. How many in 100 days?
→ 250 × 100 = 25,000 items - If a box of rice costs $45, how much is 1,000 boxes?
→ 45 × 1,000 = $45,000
Patterns (Expanded & Explained)
The number of zeros in the multiplier tells how many places the digits shift to the left:
|
Multiplication |
Zeros in Multiplier |
Number of Places Shifted |
|
×10 |
1 zero |
1 place left |
|
×100 |
2 zeros |
2 places left |
|
×1,000 |
3 zeros |
3 places left |
So:
- 34 × 10 → add 1 zero → 340
- 124 × 100 → add 2 zeros → 12,400
- 7 × 1,000 → add 3 zeros → 7,000
💡 Note: This only works cleanly with whole numbers.
Place Value Chart Demonstration (Optional Use of Board or Flashcards)
Let’s take the number 36 and multiply by 10, 100, and 1,000:
|
Digit |
HTh |
TTh |
Th |
H |
T |
O |
|
3 |
3 |
6 |
||||
|
6 |
- 36 × 10 → 360 (digits move one place left)
- 36 × 100 → 3,600 (digits move two places left)
- 36 × 1,000 → 36,000 (digits move three places left)
Learners’ Activities (Expanded)
🔹 Group Activity with Place Value Charts:
- Students receive number cards and blank place value charts.
- They place a number (e.g., 72) on the chart and shift the digits based on ×10, ×100, and ×1,000.
- Record the new values.
🔹 Real-Life Estimation Tasks:
- Scenario: "A town has 2,450 people. Estimate how many in 10 towns, 100 towns?"
→ 2,450 × 10 = 24,500
→ 2,450 × 100 = 245,000
🔹 Class Game: “Zero Tag”
- Teacher calls a base number and a multiplier (e.g., 13 and 1,000).
- Students write the product as fast as possible (13,000) and explain how they got it.
🔹 Use of Flashcards (Peer Quiz):
- Each student has a card with a base number.
- Partner gives multiplier (10, 100, 1000).
- Student quickly gives the product and explains digit shift.
🔹 Writing Exercise:
- “In your notebook, explain in your own words what happens when a number is multiplied by 10, 100, or 1,000.”
- Include examples.
Assessment Checks (Expanded)
✅ Oral/Written Questions:
- What is 34 × 10? → 340
- Solve: 124 × 100 → 12,400
- Why is 7 × 1,000 = 7,000?
- Multiply 89 by 100
- Multiply 250 by 1,000
- If 1 chair costs $40, what is the cost of 100 chairs?
✅ Table Completion (Worksheet):
|
Base Number |
Multiplier |
Product |
|
13 |
×10 |
? |
|
27 |
×100 |
? |
|
62 |
×1,000 |
? |
|
75 |
×100 |
? |
|
9 |
×1,000 |
? |
✅ Explain Your Answer Task:
- Ask learners to explain how many digits shift and why zeros are added.
Notes (Expanded & Detailed)
🔍 Key Understanding:
- Multiplying by 10, 100, or 1,000 is not about “just adding zeros” randomly—it's about shifting digits on the place value chart.
📌 Application in Real Life:
- Useful in budgeting, scaling recipes, estimating population, or calculating costs of multiple items.
📌 Helps Learners To:
- Understand number sense
- Develop mental math strategies
- Build foundation for place value and decimal operations in later grades
💡 Common Mistake to Watch:
- Students may “add zeros” without understanding the place value shift. Use charts and visuals to correct this.
C – Consolidation (Conclusion & Assessment)
Time: 5–10 minutes
Summary: Multiplying by 10s, 100s, and 1000s is quick using place value patterns
Evaluation Method (Expanded):
Exit slip/quiz: Multiply 25 × 10, 42 × 100, and 17 × 1000
Teacher will collect and provide oral feedback
Assignment (Expanded):
Solve textbook exercises on multiplication by 10, 100, and 1000
Follow-up Activity:
Create 5 real-life problems at home using multiplication by 10, 100, or 1000
Differentiation / Inclusive Strategies
Provide place value charts for struggling learners
Challenge advanced learners with larger numbers
Teacher’s Reflection (After Class)
What worked well? ___________________________________________
What needs improvement? ____________________________________
Students’ engagement level: ☑ High ☑ Medium ☑ Low