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Multiply Two-Digit Wonders!

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Lesson Plan

Multiply Two-Digit Wonders!

Students will learn and practice multiplying two-digit numbers using the area model and partial products method to build foundational arithmetic skills.

Mastering two-digit multiplication is essential for higher-level math and real-world problem-solving, like calculating costs or measurements. This lesson provides targeted practice to solidify understanding.

Audience

5th Grade Students

Time

15 minutes

Approach

Review, guided practice, and independent practice with a focus on understanding the process.

Materials

Multiply Two-Digit Wonders! Slides, Two-Digit Multiplication Practice, and Two-Digit Multiplication Answer Key

Prep

Preparation

5 minutes

Step 1

Warm-Up: Quick Recall

2 minutes

  • Teacher: Begin by asking students to quickly recall basic multiplication facts (e.g., 7x8, 5x6). Write a couple of two-digit by one-digit problems on the board (e.g., 23 x 4) and ask students to solve them mentally or on scratch paper.
    * Students: Participate in the recall and solve the warm-up problems.

Step 2

Introduction: Why Two-Digit Multiplication?

2 minutes

  • Teacher: Display the first slide of Multiply Two-Digit Wonders! Slides. Ask students: "Why do we need to learn how to multiply big numbers like 24 x 36? Where might we use this in real life?" Guide them to discuss scenarios like calculating areas, costs, or quantities.
    * Students: Share ideas and engage in discussion.

Step 3

Method Review: Area Model & Partial Products

5 minutes

  • Teacher: Use Multiply Two-Digit Wonders! Slides (Slides 2-4) to briefly review the area model and partial products method. Work through one simple example (e.g., 12 x 13) together step-by-step, emphasizing how each part connects.
    * Students: Observe and ask clarifying questions as the teacher demonstrates.

Step 4

Guided Practice: Let's Do One Together!

3 minutes

  • Teacher: Present a new problem (e.g., 21 x 14) from Multiply Two-Digit Wonders! Slides (Slide 5). Guide students to solve it with you, either on mini-whiteboards or scratch paper, using the partial products method. Circulate to provide immediate feedback.
    * Students: Work through the problem with the teacher, asking for help as needed.

Step 5

Independent Practice: Show What You Know!

3 minutes

  • Teacher: Distribute the Two-Digit Multiplication Practice worksheet. Instruct students to complete the first two problems using either method we discussed. Emphasize showing their work.
    * Students: Work independently on the worksheet.

Step 6

Wrap-Up & Next Steps

1 minute

  • Teacher: Briefly review the answers to the independent practice problems using the Two-Digit Multiplication Answer Key. Address any common misconceptions. Collect the worksheets. Reiterate the importance of practice.
    * Students: Check their work and listen to feedback. Submit worksheets.
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Slide Deck

Multiply Two-Digit Wonders!

Why does it matter?

  • When do we use big numbers in real life?
  • Think about shopping, building, or even planning a party!

Welcome students and introduce the topic. Ask them to think about why multiplying larger numbers is useful in real life before showing the slide content. Connect it to money, area, or counting large groups.

Area Model: A Visual Way to Multiply

Imagine you have a rectangle, and you want to find its area.

  • Break down your numbers by tens and ones (e.g., 20 + 4 and 30 + 6).
  • Draw a grid to multiply each part.
  • Add up all the smaller products!

Example: 24 x 36

Review the Area Model method. Draw a simple example (like 12 x 13) on the board alongside the slide, breaking it down into smaller, easier multiplications. Emphasize the grid and adding the 'partial products' at the end.

Partial Products: Breaking It Down

It's like having a conversation with each part of the numbers!

To multiply 24 x 36:

  1. Multiply the ones digit of the bottom number by both parts of the top number (6 x 4, then 6 x 20).
  2. Multiply the tens digit of the bottom number by both parts of the top number (30 x 4, then 30 x 20).
  3. Add up all your 'partial products' to get the total!

Example: 24 x 36

Introduce or review Partial Products. This is a crucial step before moving to the standard algorithm. Work through 24 x 36 using this method, showing each step clearly. Highlight that we are multiplying each part of one number by each part of the other number.

Let's Practice Together!

Problem: 21 x 14

  • How would you set this up?
  • What are your first steps?
  • Remember to multiply each part!

Work through this problem step-by-step with your teacher!

Work through a guided example with the students. Have them try to follow along on their own paper. Encourage them to choose either the area model or partial products, whichever feels more comfortable, but guide them towards partial products for this example as it's often more efficient for written work. Provide support as needed.

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Worksheet

Two-Digit Multiplication Practice

Instructions: Solve the following two-digit multiplication problems. Show your work using either the Area Model or Partial Products method.

Problem 1

23 x 15













Problem 2

42 x 11













Problem 3

35 x 24













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Answer Key

Two-Digit Multiplication Answer Key

Here are the step-by-step solutions for the practice problems.

Problem 1: 23 x 15

Using Partial Products:

  • 5 x 3 = 15
  • 5 x 20 = 100
  • 10 x 3 = 30
  • 10 x 20 = 200
  • Total: 15 + 100 + 30 + 200 = 345



Problem 2: 42 x 11

Using Partial Products:

  • 1 x 2 = 2
  • 1 x 40 = 40
  • 10 x 2 = 20
  • 10 x 40 = 400
  • Total: 2 + 40 + 20 + 400 = 462



Problem 3: 35 x 24

Using Partial Products:

  • 4 x 5 = 20
  • 4 x 30 = 120
  • 20 x 5 = 100
  • 20 x 30 = 600
  • Total: 20 + 120 + 100 + 600 = 840
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