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Multiply Two-Digit Wonders

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Lesson Plan

Multiply Two-Digit Wonders

Students will be able to multiply two-digit numbers by one-digit numbers using the 'break apart' strategy.

Understanding how to multiply two-digit numbers by one-digit numbers is a fundamental skill that builds confidence and lays the groundwork for more advanced multiplication and problem-solving in everyday life.

Audience

3rd Grade Students

Time

15 minutes

Approach

Direct instruction, guided practice, and independent practice using the 'break apart' strategy.

Materials

Warm-Up Activity, Slide Deck: Multiply Two-Digit Wonders, Worksheet: Two-Digit Challenge, Answer Key: Two-Digit Challenge, Whiteboard or Projector, and Markers or Pens

Prep

Teacher Preparation

10 minutes

Step 1

Warm-Up: Fact Recall (2 minutes)

2 minutes

  • Display a few basic multiplication facts (e.g., 3x4, 5x6) for students to solve quickly.
    - Briefly review answers as a class.
    - Introduce the day's topic: multiplying bigger numbers!
    - Refer to the Warm-Up Activity.

Step 2

Introduction: Break Apart Strategy (3 minutes)

3 minutes

  • Present the title slide from the Slide Deck: Multiply Two-Digit Wonders.
    - Explain that today they'll learn a strategy called 'break apart' to multiply two-digit by one-digit numbers.
    - Guide students through the first example on the slide, breaking down a two-digit number into tens and ones (e.g., 15 x 3 becomes (10 x 3) + (5 x 3)).

Step 3

Guided Practice: Let's Do It Together (5 minutes)

5 minutes

  • Work through 2-3 additional examples from the Slide Deck: Multiply Two-Digit Wonders as a class.
    - Encourage students to participate by suggesting how to break apart the numbers and solve each part.
    - Ask questions like: 'How can we break apart this two-digit number?' and 'What are the two smaller multiplication problems?'

Step 4

Independent Practice: Your Turn! (4 minutes)

4 minutes

  • Distribute the Worksheet: Two-Digit Challenge.
    - Instruct students to complete the first few problems on their own using the 'break apart' strategy.
    - Circulate around the room to provide individual support and check for understanding.

Step 5

Cool-Down: Quick Check (1 minute)

1 minute

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Slide Deck

Multiply Two-Digit Wonders

How do we multiply numbers like 15 x 3?

Get ready to break it down!

Welcome students and introduce the lesson. Explain that today we'll learn a fun way to multiply bigger numbers.

The 'Break Apart' Strategy

Breaking it Down!

To multiply a 2-digit number by a 1-digit number:

  1. Break apart the 2-digit number into tens and ones.
  2. Multiply each part by the 1-digit number.
  3. Add the products together!

Example: 15 x 3

  • Break 15 into 10 and 5.
  • (10 x 3) + (5 x 3)
  • 30 + 15
  • Answer: 45

Introduce the 'break apart' strategy. Use an example like 15 x 3. Explain breaking 15 into 10 + 5. Show how to multiply each part by 3 and then add the results.

Let's Practice Together! (1)

Try this one: 23 x 4

  • How would you break apart 23?



  • What are the two multiplication problems?



  • What is the final answer?



Guided practice example 1. Ask students how to break apart 23. Guide them through multiplying 20x4 and 3x4.

Let's Practice Together! (2)

Another one: 31 x 5

  • How would you break apart 31?



  • What are the two multiplication problems?



  • What is the final answer?



Guided practice example 2. Ask students how to break apart 31. Guide them through multiplying 30x5 and 1x5.

Your Turn! Independent Practice

Show what you know!

  • Use the break apart strategy for the problems on your worksheet.
  • Work quietly and do your best!
  • Remember to break the two-digit number into tens and ones.

Introduce the independent practice. Explain that they will now try some problems on their own using the same strategy.

Quick Check & Wrap Up!

What did you learn today?

  • How does the break apart strategy help us multiply?
  • Can you give an example of a problem you could solve?

Great job everyone! You are two-digit multiplication wonders!

Wrap up the lesson by asking students to share what they learned. Reinforce the 'break apart' strategy.

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Warm Up

Warm-Up: Multiplication Fact Recall

Solve these multiplication facts as quickly as you can!

  1. 4 x 5 =


  2. 7 x 2 =


  3. 6 x 3 =


  4. 8 x 4 =


  5. 9 x 1 =


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Worksheet

Worksheet: Two-Digit Challenge

Directions: Use the "break apart" strategy to solve each multiplication problem. Show your work!

Example: 15 x 3 = (10 x 3) + (5 x 3) = 30 + 15 = 45

  1. 12 x 4











  2. 21 x 3











  3. 16 x 2











  4. 34 x 1











  5. 25 x 3











  6. 13 x 5











  7. 42 x 2











  8. 18 x 3











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Answer Key

Answer Key: Two-Digit Challenge

Directions: Use the "break apart" strategy to solve each multiplication problem. Show your work!

  1. 12 x 4

    • Break apart 12 into 10 and 2.
    • (10 x 4) + (2 x 4)
    • 40 + 8
    • Answer: 48



  2. 21 x 3

    • Break apart 21 into 20 and 1.
    • (20 x 3) + (1 x 3)
    • 60 + 3
    • Answer: 63



  3. 16 x 2

    • Break apart 16 into 10 and 6.
    • (10 x 2) + (6 x 2)
    • 20 + 12
    • Answer: 32



  4. 34 x 1

    • Break apart 34 into 30 and 4.
    • (30 x 1) + (4 x 1)
    • 30 + 4
    • Answer: 34



  5. 25 x 3

    • Break apart 25 into 20 and 5.
    • (20 x 3) + (5 x 3)
    • 60 + 15
    • Answer: 75



  6. 13 x 5

    • Break apart 13 into 10 and 3.
    • (10 x 5) + (3 x 5)
    • 50 + 15
    • Answer: 65



  7. 42 x 2

    • Break apart 42 into 40 and 2.
    • (40 x 2) + (2 x 2)
    • 80 + 4
    • Answer: 84



  8. 18 x 3

    • Break apart 18 into 10 and 8.
    • (10 x 3) + (8 x 3)
    • 30 + 24
    • Answer: 54



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Cool Down

Cool-Down: Multiply Your Learning!

Directions: Answer the following question about today's lesson.

  1. Explain in your own words how the "break apart" strategy helps you multiply 2-digit by 1-digit numbers. Give an example if you like!












  2. Solve this problem using the break apart strategy: 14 x 2







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