Lesson Plan
Multiplication Block Party Lesson Plan
Students will learn to decompose two-digit numbers into tens and ones and use area models to compute partial products and multiply efficiently.
Visualizing multiplication via area models builds deep conceptual understanding, increases fluency with multi-digit operations, and sets the stage for algebraic reasoning.
Audience
5th Grade
Time
30 minutes
Approach
Visual modeling with guided then independent practice.
Materials
- Graph Paper, - Base-Ten Blocks, - Individual Whiteboards and Dry-Erase Markers, - Document Camera or Projector, - Area Model Explanation Slide Deck, and - Area Model Multiplication Practice Worksheet
Prep
Prepare Materials
10 minutes
- Print enough copies of the Area Model Multiplication Practice Worksheet for each student
- Ensure the Area Model Explanation Slide Deck is loaded and functioning on the projector
- Gather base-ten blocks, graph paper, whiteboards, and markers
- Review the slide deck and worksheet to familiarize yourself with examples and instructions
Step 1
Warm-Up
5 minutes
- Write two simple multiplication problems (e.g., 6×4, 12×3) on the board and ask students to solve mentally
- Invite volunteers to share strategies and answers
- Link to area model: explain that breaking numbers into parts can simplify multiplication
Step 2
Direct Instruction
7 minutes
- Project the Area Model Explanation Slide Deck
- Demonstrate decomposing 23×15 into (20+3) and (10+5)
- Draw an area model grid, label each section, and calculate 20×10, 20×5, 3×10, 3×5
- Sum the partial products to find the total
Step 3
Guided Practice
7 minutes
- Present a new problem (e.g., 34×12) on the projector
- Guide students in decomposing numbers and sketching the grid
- Use base-ten blocks or graph paper to represent each part
- Calculate each partial product together and sum them
Step 4
Independent Practice
7 minutes
- Distribute the Area Model Multiplication Practice Worksheet
- Students complete several multi-digit problems using area models on graph paper
- Teacher circulates, offers prompts, and checks for correct decomposition and sums
Step 5
Cool-Down
3 minutes
- Ask students to turn to a partner and share one strategy they used and one question they have
- Invite 2–3 volunteers to share their insights or remaining challenges
Step 6
Exit Ticket
1 minute
- On a sticky note or mini whiteboard, students solve 47×6 using an area model or mental strategy
- Collect responses to gauge understanding and inform next steps
Slide Deck
Area Model Multiplication
Visualizing Two-Digit Multiplication with Area Models
Welcome students and introduce the area model for multiplication. Explain how visuals can make multi-digit multiplication easier to understand.
Decomposing Numbers
Break each factor into tens and ones:
• 23 = 20 + 3
• 15 = 10 + 5
Explain that any two-digit number can be split into tens and ones. Model the decomposition.
Step 1: Draw the Grid
- Draw a rectangle.
- Split into 2 columns and 2 rows.
- Label columns with the tens and ones of the first factor.
- Label rows with the tens and ones of the second factor.
Show how to draw the rectangle grid, with columns and rows matching the decomposed parts.
Example Setup: 23 × 15
• Top labels: 20 | 3
• Side labels: 10 | 5
Label the example grid for 23 × 15, but leave the inside blank for now.
Step 2: Find Partial Products
Compute inside each box:
• 20 × 10 = 200
• 20 × 5 = 100
• 3 × 10 = 30
• 3 × 5 = 15
Walk through computing each smaller rectangle’s area.
Step 3: Add Them Up
200 + 100 + 30 + 15 = 345
Show how adding the four areas gives the final answer.
Why It Works
The grid represents (20 + 3) × (10 + 5).
Distribute:
20×10 + 20×5 + 3×10 + 3×5 = 345
Connect the model to the distributive property.
Try It Together
Use the area model for 34 × 12:
- Decompose: 34 = 30 + 4, 12 = 10 + 2
- Draw and label the grid
- Find partial products
- Sum to get the product
Guide students step-by-step through this next example.
Your Turn
On your whiteboard, model and solve:
47 × 6
(Hint: 47 = 40 + 7; 6 = 6 + 0)
Invite students to work on whiteboards. Circulate and prompt as needed.
Key Takeaways
• Decompose into tens and ones
• Draw the area model grid
• Multiply each part
• Add all partial products
Next: Practice on the worksheet
Recap the steps and remind students of the upcoming worksheet.
Worksheet
Area Model Multiplication Practice Worksheet
Name: ______________________ Date: ___________
Instructions
- Decompose each factor into tens and ones.
- Draw an area model grid on your graph paper: columns for the parts of the first factor, rows for the parts of the second factor.
- Calculate each partial product and record below.
- Add all partial products to find the final product.
(Refer back to the Area Model Explanation Slide Deck if you need a refresher.)
Example (together)
Problem: 23 × 15
- Decompose:
23 = ____ + ____ ; 15 = ____ + ____ - Draw a 2×2 grid on graph paper and label:
• Columns: ____, ____
• Rows: ____, ____ - Partial products:
____ × ____ = ____
____ × ____ = ____
____ × ____ = ____
____ × ____ = ____ - Sum of partial products: ____ + ____ + ____ + ____ = ____
Guided Practice
1) 24 × 13
- Decompose and record:
24 = ____ + ____ ; 13 = ____ + ____ - Draw and label your grid, then fill in:
____ × ____ = ____
____ × ____ = ____
____ × ____ = ____
____ × ____ = ____ - Sum of partial products: ________________________________________
2) 36 × 15
- Decompose:
36 = ____ + ____ ; 15 = ____ + ____ - Partial products:
____ × ____ = ____
____ × ____ = ____
____ × ____ = ____
____ × ____ = ____ - Total product: _________________________________________________
Independent Practice
Use your own graph paper to draw and solve each with an area model. Show your work below each problem.
3) 47 × 8
__________________________________________________________________
4) 52 × 27
__________________________________________________________________
5) 68 × 34
__________________________________________________________________
6) Word Problem: A rectangular garden measures 46 feet in length and 23 feet in width.
Use an area model to find the total number of square feet in the garden.
__________________________________________________________________
Great work! Be prepared to share one strategy you used with a partner.
Answer Key
Area Model Multiplication Answer Key
Below are complete solutions for the Example, Guided Practice, and Independent Practice problems. Each solution shows the decomposition, area‐model setup, partial products, and final sum.
Example (together)
Problem: 23 × 15
- Decompose each factor:
- 23 = 20 + 3
- 15 = 10 + 5
- Label the 2×2 grid:
- Columns: 20 | 3
- Rows: 10 | 5
- Compute each partial product:
- 20 × 10 = 200
- 20 × 5 = 100
- 3 × 10 = 30
- 3 × 5 = 15
- Sum all partial products:
200 + 100 + 30 + 15 = 345
Guided Practice
1) 24 × 13
- Decompose:
- 24 = 20 + 4
- 13 = 10 + 3
- Grid labels:
- Columns: 20 | 4
- Rows: 10 | 3
- Partial products:
- 20 × 10 = 200
- 20 × 3 = 60
- 4 × 10 = 40
- 4 × 3 = 12
- Sum:
200 + 60 + 40 + 12 = 312
2) 36 × 15
- Decompose:
- 36 = 30 + 6
- 15 = 10 + 5
- Grid labels:
- Columns: 30 | 6
- Rows: 10 | 5
- Partial products:
- 30 × 10 = 300
- 30 × 5 = 150
- 6 × 10 = 60
- 6 × 5 = 30
- Sum:
300 + 150 + 60 + 30 = 540
Independent Practice
3) 47 × 8
- Decompose:
- 47 = 40 + 7
- 8 = 8 + 0
- Grid labels:
- Columns: 40 | 7
- Rows: 8 | 0
- Partial products:
- 40 × 8 = 320
- 40 × 0 = 0
- 7 × 8 = 56
- 7 × 0 = 0
- Sum:
320 + 0 + 56 + 0 = 376
4) 52 × 27
- Decompose:
- 52 = 50 + 2
- 27 = 20 + 7
- Grid labels:
- Columns: 50 | 2
- Rows: 20 | 7
- Partial products:
- 50 × 20 = 1000
- 50 × 7 = 350
- 2 × 20 = 40
- 2 × 7 = 14
- Sum:
1000 + 350 + 40 + 14 = 1404
5) 68 × 34
- Decompose:
- 68 = 60 + 8
- 34 = 30 + 4
- Grid labels:
- Columns: 60 | 8
- Rows: 30 | 4
- Partial products:
- 60 × 30 = 1800
- 60 × 4 = 240
- 8 × 30 = 240
- 8 × 4 = 32
- Sum:
1800 + 240 + 240 + 32 = 2312
6) Word Problem: Garden Area
A garden is 46 ft by 23 ft. Find its area.
- Decompose:
- 46 = 40 + 6
- 23 = 20 + 3
- Grid labels:
- Columns: 40 | 6
- Rows: 20 | 3
- Partial products:
- 40 × 20 = 800
- 40 × 3 = 120
- 6 × 20 = 120
- 6 × 3 = 18
- Sum:
800 + 120 + 120 + 18 = 1058 square feet
This completes the answer key for the Area Model Multiplication Practice Worksheet. Feel free to use these step‐by‐step solutions for grading or to guide students through the reasoning process.