Data Detectives Slides Training Mission
Data Detectives
Mastering Scaled Graphs & Tables
Mission Objectives
1
Collect data in categories.
2
Represent data using frequency tables, picture graphs, and bar graphs.
3
Solve one and two-step "How many more/less" problems.
"Good detectives don't guess—they use data!"
Frequency Tables
A Frequency Table uses numbers to show how many times something happens.
Favorite Detective Tools
Tool Tally Frequency Magnifying Glass ~ Flashlight ~ Notebook ~
How many notebooks were chosen?
Scaled Picture Graphs
THE KEY IS KEY!
A Scaled Picture Graph uses pictures to represent data.
Why use a scale?
Sometimes we have too much data to draw a picture for every single one! A scale tells us what each picture stands for.
Footprints Found at Crime Scene
Kitchen
Garden
KEY: = 2 Footprints
Detective Brainstorm
Look back at the Footprint Graph:
Solution Step 1:
Kitchen: 3 pictures × 2 = 6 footprints
Solution Step 2:
Garden: 5 pictures × 2 = 10 footprints
10 - 6 = 4 more footprints!
Scaled Bar Graphs
A Scaled Bar Graph uses bars of different heights to show data.
Watch the Axis!
The vertical or horizontal axis shows the scale. Sometimes it counts by 2s, 5s, or 10s!
20 15 10 5 0
15
10
18?
Final Detective Challenge
The Case of the Missing Cookies
The cafeteria found:
Step 1:
How many more Sugar cookies were there than Oatmeal Raisin?
Step 2:
If 10 Chocolate Chip cookies are eaten, how many are left?
Case Files Guided Notes Case Files: Guided Notes
Detective Training Program
Detective:
Date:
The Mission
Detectives and interpret data using tables, scaled graphs, and scaled graphs.
1. Frequency Tables
A frequency table shows how many times a value occurs. We often use tallies to count.
Example: Detective Tool Choices
Tool Tally Area Frequency Magnifying Glass ~ Flashlight ~ Notebook ~
2. Scaled Picture Graphs
The Key is Critical! Each picture represents more than one item. Multiply the pictures by the scale.
Footprints Found at Crime Scene
Kitchen
Garden
KEY: = 2 Footprints
A
How many footprints were in the Kitchen?
B
How many more footprints in Garden than Kitchen?
3. Scaled Bar Graphs
Check the axis (the numbers on the side) to see the scale.
Interpret the Height:
If the axis counts by 5s, a bar that stops exactly between 10 and 15 represents:
Example Axis (Scale of 5)
20151050
Independent Case Check
Detective Sarah found 20 blue pieces of evidence and 15 red pieces.
A. How many more blue than red?
B. What is the total of all pieces?
"Evidence is everything. Keep your data clear!" — Head Detective
Field Report Practice Field Report Practice
Official Junior Detective Assignment
Detective:
Detective's Quick Ref
Scale: Multiply pictures by the key.
Frequency: The total number in a group.
Axis: The side of a bar graph with numbers.
Difference: Subtract to find "how many more".
Task 1: Collect & Organize
Junior detectives counted clues found on patrol:
12 Footprints
16 Fingerprints
8 Lost Keys
4 Secret Letters
Category Tally Area Frequency Footprints Fingerprints Lost Keys Secret Letters
Task 2: Scaled Picture Graph
Draw a Scaled Picture Graph using your Task 1 data. Check the Key!
Evidence Found on Patrol
Footprints
Fingerprints
Lost Keys
Secret Letters
KEY:
= 4 Clues
Task 3: Evidence Interpretation
Detective Badges Earned
20151050
AlphaBetaGamma
1. How many more badges did Team Gamma earn than Team Beta?
2. What is the total number of badges earned by all teams?
3. If Team Alpha loses 5 badges, how many will they have left?
Case Closed Answer Key Case Closed: Answer Key
Teacher Facilitation Guide
Standard: NC.3.MD.3
1. Case Files: Guided Notes Key
The Mission (Definitions)
Detectives collect and interpret data using frequency tables, scaled picture graphs, and scaled bar graphs.
Frequency Table
Notebook Frequency: 12
Picture Graph Task
A (Kitchen): 6
B (Garden Diff): 4 more
Bar Graph Axis Check
Value between 10 and 15 = 12 or 13
Independent Check
1. How many more: 5 2. Total: 35
2. Field Report Practice Key
Task 1: Frequency Table
Category Frequency Footprints 12 Fingerprints 16 Lost Keys 8 Secret Letters 4
Task 2: Pictures (Scale 4)
• Footprints: 3 icons
• Fingerprints: 4 icons
• Lost Keys: 2 icons
• Secret Letters: 1 icon
Task 3: Interpretation
1. 10 more badges
2. 45 badges total
3. 10 badges left
3. Mystery Task Cards Key
Case #001
25 - 15 = 10 magnets
Case #002
20 + 30 + 40 = 90 apples
Case #003
8 + 12 + 4 = 24 birds
Case #004
40 - 28 = 12 more
Teacher Implementation Tips
• Conceptual Check: Ask students, "If each icon represented 2 clues instead of 4, would we need more or fewer icons?"
• Task Cards: Use these for a "Scoot" game or a scavenger hunt to get students moving!
• Step-by-Step: For Case #004, ensure students add the first two categories before subtracting from the Wizard's total.
Mystery Task Cards Mystery Task Cards
Advanced Data Interpretation Training
NC.3.MD.3 Mastery
Case #001
The Missing Magnets
Magnets Found
Class A
Class B
KEY: = 5 Magnets
How many more magnets did Class B find than Class A?
Show Work
Case #002
The Snack Caper
Apples Eaten
Number of Apples
403020100
MonTueWed
What is the total number of apples eaten in 3 days?
Show Work
Case #003
The Bird Watch
"I saw 8 Blue Jays, 12 Robins, and 4 Woodpeckers near the fountain."
Bird Freq. Blue Jay Robin Woodpecker
How many birds did the detective see in total?
Show Work
Case #004
The Costume Contest
Votes Received
18 Hero
10 Robot
40 Wizard
How many more votes for Wizard than Hero & Robot combined?
Show Work
Cut these cards out for a "Case File Scavenger Hunt"!
