Lab Teacher Guide
Teacher Facilitation Guide
Mixed Number Multiplication Lab
Grade 5 • Math
Learning Objective
Students will fluently multiply whole numbers by mixed numbers using the standard algorithm, specifically utilizing side calculations to organize work.
Pacing & Structure
5 min
Warm-up: Mental Math
Multiplying whole numbers by unit fractions (e.g., \(6 \times \frac{1}{2}\), \(10 \times \frac{1}{5}\)). Focus on the concept of "of".
10 min
Video & Strategy Introduction
Watch the "Yellow Note" technique video. Pause for conversion and division checks.
25 min
Side-Calculation Stations
Structured practice using the provided worksheet. Students must use the yellow side boxes for all scratch work.
5 min
Exit Ticket
Solve \(3 \times 1 \frac{2}{5}\) to demonstrate procedural fluency and organizational skills.
Teaching Moments
- The "Why": Ask students why we write the whole number over 1. (Answer: To treat it as a fraction so we can multiply across numerators and denominators without confusion).
- Organization: Emphasize that the "Yellow Note" isn't "extra work"—it's a tool to keep the main equation clean and prevent silly errors.
- Simplification: Remind students to check if their final mixed number can be simplified (e.g., \(13 \frac{4}{8} \to 13 \frac{1}{2}\)).
Common Pitfalls
The "Whole Only" Error
Students multiply the whole number by the whole part of the mixed number but forget the fractional part.
Denominator Multiplication
Multiplying the whole number by both the numerator and denominator (e.g., \(2 \times \frac{1}{3} = \frac{2}{6}\)). Using \( \frac{2}{1} \) fixes this.
Answer Key
Worksheet: Side-Calculation Stations
1. \(5 \times 2 \frac{1}{3}\) 11 \(\frac{2}{3}\)
2. \(8 \times 1 \frac{3}{4}\) 14 (or 14 \(\frac{0}{4}\))
3. \(4 \times 3 \frac{2}{5}\) 13 \(\frac{3}{5}\)
4. \(6 \times 2 \frac{5}{6}\) 17 (or 17 \(\frac{0}{6}\))
5. \(2 \times 4 \frac{7}{10}\) 9 \(\frac{2}{5}\) (9 \(\frac{4}{10}\))
6. \(3 \times 2 \frac{5}{8}\) 7 \(\frac{7}{8}\)
Exit Ticket Solution
Problem: \(3 \times 1 \frac{2}{5}\)
- Convert: \(1 \frac{2}{5} = \frac{7}{5}\)
- Setup: \(\frac{3}{1} \times \frac{7}{5} = \frac{21}{5}\)
- Convert Back: \(21 \div 5 = 4\) R \(1\)
- Answer: \(4 \frac{1}{5}\)
Mixed Number Masters Slides
Math Lab
Mixed Number Masters
Multiplying Whole Numbers & Mixed Numbers
Use Your Side Notes!
Mental Math Warm-up
Think of multiplication as "groups of". What is the total?
A 6 × ½ = ?
B 10 × ⅕ = ?
C 12 × ¼ = ?
Challenge Question:
"How many halves are in 6 whole water bottles?"
Watch & Learn
Embedded media
Look For:
- The "Yellow Notes" on the side.
- What happens to the whole number?
- How many steps are there?
Think Pair Share
"Why does the video write the whole number over 1?"
The "Yellow Note" Strategy
1
CONVERT
Change the mixed number to an improper fraction.
2 ½ → 5/2
2
SET UP & SOLVE
Write whole number over 1 and multiply across.
7/1 × 5/2 = 35/2
3
SIMPLIFY
Convert back to a mixed number using division.
35 ÷ 2 = 17 ½
Guided Practice
Grab your whiteboards!
Problem: 4 × 3 ¾
Step 1: Convert 3 ¾
Step 2: Multiply &frac41; × ?
Step 3: Division Check!
Your Work Area
Activity Time!
Side-Calculation Stations
Get your Worksheet
MUST use the Yellow Note boxes for steps
Work with your station partner
Side Calculation Stations Worksheet
Side-Calculation Stations
Mixed Number Multiplication Lab
Name:
Date:
Directions: Solve each problem below. You must show your work in the "Yellow Note" side-calculation boxes. Use the first box for converting to an improper fraction and the second box for long division.
5 × 2 ⅓
Final:
Side Note: Conversion
Side Note: Division/Simplifying
8 × 1 ¾
Final:
Side Note: Conversion
Side Note: Division/Simplifying
4 × 3 ⅖
Final:
Side Note: Conversion
Side Note: Division/Simplifying
6 × 2 ⅚
Final:
Side Note: Conversion
Side Note: Division/Simplifying
A small recipe calls for 4 &frac7{10} cups of flour. If a baker wants to make 2 batches, how many cups of flour will they need in total?
2 × 4 &frac7{10}
Final:
Side Note: Conversion
Side Note: Division/Simplifying
