Decimal Workshop Slides Decimal Blueprints
Lesson 1: Redefining the Whole
What if I told you...
This single small cube isn't "one" anymore.
Cube
It's actually just one tiny piece of a much larger blueprint.
The New Blueprint
The Flat
1
One Whole
The Rod
0.1
One Tenth
The Cube
0.01
One Hundredth
Blueprint Challenge
How would you build the number 1.23?
?
Flats
?
Rods
?
Cubes
Speaking Decimal
0.1
"One Tenth"
0.01
"One Hundredth"
0.45
"Forty-five Hundredths"
Decimal Building Worksheet Decimal Blueprint
Lesson 1: Building with Parts
NAME:
DATE:
FLAT
1.0
ROD
0.1
CUBE
0.01
Part 1: Build & Write
Use your blocks to build these decimals. Then, count the pieces and write the totals.
1.42
Flats (Wholes)
Rods (Tenths)
Cubes (Hundredths)
0.58
Flats (Wholes)
Rods (Tenths)
Cubes (Hundredths)
2.07
Flats (Wholes)
Rods (Tenths)
Cubes (Hundredths)
Part 2: Speak Decimal
Read the decimal out loud to a partner, then write how we say it in words.
0.15
1.04
Master Builder Question
If you have 10 rods, what can you trade them for? Why?
Redefining Whole Teacher Guide Facilitator's Blueprint
Lesson 1: Redefining the Whole
Time Estimate 45-60 MIN
Learning Objectives
Students will redefine the "Flat" as 1.0, the "Rod" as 0.1, and the "Cube" as 0.01.
Students will represent decimal values up to the hundredths place using physical manipulatives.
Students will articulate decimal names correctly (e.g., "fourteen hundredths" instead of "point one five").
Gear List
Base-ten block sets
Decimal Workshop Slides
Decimal Building Worksheet
Individual whiteboards
Instructional Steps
Step 1: The Hook (5 min)
Hold up a unit cube. Ask students: "In 4th grade, what did we call this?" (Wait for "one"). Tell them that today, the rules of the workshop have changed. The cube is no longer 1. It is a tiny crumb of 1.
Teacher Tip: Watch for students who struggle with the conceptual shift. Use the "blueprint" analogy—the flat is the completed floor plan (1 whole), while rods and cubes are the lumber and nails used to build it.
Step 2: Redefining (15 min)
Use the Decimal Workshop Slides to define the new values. Have students physically hold each block as you define it. Reinforce the relationship: "It takes 10 rods to make a flat. It takes 100 cubes to make a flat."
Guiding Question
"If I have 2 rods and 3 cubes, how much of a whole do I have?"
Check for Understanding
Have students hold up the block that represents 0.01.
Step 3: Build & Record (25 min)
Distribute the Decimal Building Worksheet . Students work in pairs or independently to build the numbers listed. Circulate and ask students to "name" their decimals using place value terms.
Support Strategies
For Students with Learning Disabilities:
Use color-coded blocks (if available) or color-coded mats where the tenths column is blue and the hundredths column is orange to match the slides.
Extension:
Ask students to build decimals with values > 2 (e.g., 2.35) and explain why we need more than two flats.
Decimal Showdown Worksheet Decimal Showdown
Lesson 2: The Battle of the Blocks
NAME:
DATE:
How to Play
Build both decimals using your blocks.
Place them side-by-side on your desk.
Look at which one uses more material (more flats or rods).
Write the correct symbol: < > =
Decimal A
0.5
?
Comparison
Decimal B
0.12
Decimal A
0.09
?
Comparison
Decimal B
0.2
Decimal A
1.03
?
Comparison
Decimal B
0.98
Decimal A
0.40
?
Comparison
Decimal B
0.4
The "Secret" for Success
Sometimes, a "long" decimal like 0.125 looks bigger than 0.5. After using your blocks, why is that wrong?
Decimal Showdown Cards Decimal Showdown: Ordering Cards
Teacher Note: Cut these cards out for groups. Students must arrange them in order from LEAST to GREATEST using blocks to verify.
0.3
Card A
0.15
Card B
0.09
Card C
0.21
Card D
1.02
Card E
0.5
Card F
Workspace Task
Arrange cards -> Build to Prove -> Record on Board
Decimal Bank Mat The Decimal Bank
Place Value
Deposit Mat
Wholes
1 .
(Flats)
Tenths
. 1
(Rods)
Hundredths
. 01
(Cubes)
x10
Trade 10 Cubes for 1 Rod
x10
Trade 10 Rods for 1 Flat
Decimal Bank Addition Worksheet Bank Deposit Log
Lesson 3: Adding with Trades
NAME:
DATE:
The 10-Unit Rule
Whenever you have 10 small pieces in a column, you MUST trade them for 1 larger piece in the next column.
Transaction 1
0.14
Final Total
Transaction 2 (Trade Alert!)
0.38
Did you trade 10 cubes?
Transaction 3
0.71
Did you trade 10 rods?
The Auditor's Check
Why is it important to trade 10 small pieces instead of just having 13 rods in the Tenths column?
Candy Bar Subtraction Worksheet The Candy Shop
Lesson 4: Breaking the Bar
CASHIER:
DATE:
1 WHOLE BAR
The Challenge
You have whole candy bars (Flats) and loose pieces (Rods & Cubes). When a customer wants to buy 0.35 of a bar, but you only have a whole bar, you must break it apart to give them their share!
Customer Order 1
1.48 - 0.23 = ____
Did you need to break anything?
Customer Order 2 (Break a Rod!)
Start with 0.52. Subtract 0.25. (You'll need more cubes!)
0.52 - 0.25 = ____
Action Step:
"I broke 1 Rod into ____ Cubes."
Customer Order 3 (Break a Flat!)
Start with 1.30. Subtract 0.50.
1.30 - 0.50 = ____
Action Step:
"I broke 1 Flat into ____ Rods."
Shopkeeper's Reflection
Why do we "break" (decompose) a larger block into smaller ones instead of just adding more small ones from the box?
Subtraction Exit Ticket Exit Ticket
Lesson 4: Subtraction Check
Builder Name:
1 Show Your Work
Solve 1.2 - 0.5 using the "Break a Whole" strategy.
Sketch Your Blocks Here
2 Explain It
When you subtract 0.5 from 1.2, why do you have to break the "Flat"?
How do you feel?
Blueprint to Algorithm Notes Blueprint to Numbers
Lesson 5: Bridging the Gap
ENGINEER:
DATE:
Step 1: Drawing the Math
We don't always have blocks. We can draw a quick sketch instead!
Sketch a Square for
1.0
Sketch a Line for
0.1
Sketch a Dot for
0.01
Step 2: Lining Up the Blueprint
When we write numbers, we must align the decimal points. This ensures Wholes stay with Wholes and Tenths stay with Tenths.
Wrong Way
1.42
(The points don't match!)
Right Way
1.42
(Points are in a straight line!)
Try It: Sketch & Calculate
Solve: 0.45 + 0.32
Sketch Area
Lined Up Math
________
Decimal Mastery Assessment Final Blueprint Check
Decimal Operations Assessment
NAME:
Section 1: The Blueprint Map
1. Draw a sketch of 1.25 below.
2. Write 0.42 in words.
Section 2: Calculations
Line up your decimals carefully!
0.34 + 0.52
0.58 + 0.65
1.87 - 0.45
1.2 - 0.4
Section 3: Showdown
0.6
?
0.18
