Clue Crackers Worksheet CASE FILE #100
CLUE CRACKERS
Math Detective Agency • Word Problems within 100
DETECTIVE: ___________________
DATE: ___________
STATUS: [ ACTIVE CASE ]
YOUR DETECTIVE TOOLBELT: THE C.U.B.E.S. STRATEGY
C
Circle Numbers
U
Underline Question
B
Box Action Words
Evaluate & Plan
Solve & Check
CASE FILE 01: THE GOLDEN KEYS
Detective Leo has 48 shiny brass keys. He finds 25 more keys hidden inside a dusty old drawer. How many keys does Detective Leo have in total?
CUBES Steps Done:
Circle Numbers Underline Question Box Clues Evaluate
Show Model or Drawing Here:
Equation:
Complete Sentence Answer:
CASE FILE 02: THE FUGITIVE FOOTPRINTS
Officer Maya spotted 64 mysterious muddy footprints on the garden path. By noon, 38 of those footprints had washed away in the rain. How many footprints are still visible?
CUBES Steps Done:
Circle Numbers Underline Question Box Clues Evaluate
Show Model or Drawing Here:
Equation:
Complete Sentence Answer:
CLUE CRACKERS WORKSHEET • STUDENT EDITION PAGE 1 OF 2
CASE FILE #100
CLUE CRACKERS
Math Detective Agency • Active Investigations
DETECTIVE: ___________________
[ SECURE FILE ]
CASE FILE 03: THE COIN BANDIT
The central bank vault held 92 shining golden coins. A sneaky bandit took some coins, leaving only 54 golden coins left behind. How many coins did the bandit steal?
CUBES Steps Done:
Circle Numbers Underline Question Box Clues Evaluate
Show Model or Drawing Here:
Equation:
Complete Sentence Answer:
CASE FILE 04: SECRET MESSAGES
Agent Maya decoded 37 secret messages on Monday and 45 messages on Tuesday. If she needs to decode 100 messages in total, how many more messages does she have left to decode?
CUBES Steps Done:
Circle Numbers Underline Question Box Clues Evaluate
Show Model or Drawing Here:
Equation:
Complete Sentence Answer:
CLUE CRACKERS WORKSHEET • STUDENT EDITION PAGE 2 OF 2
Clue Crackers Answers ANSWER KEY • SECURE
CLUE CRACKERS
★ TEACHER ANSWER KEY ★ Word Problems within 100
DETECTIVE: MASTER SOLVER
DATE: EXEMPLAR
STATUS: [ CASE SOLVED ]
C.U.B.E.S. STRATEGY APPLICATION
C Circle Numbers
U Underline Question
B Box Action Words
Evaluate/Plan
Solve & Check
CASE FILE 01: THE GOLDEN KEYS
Detective Leo has 48 shiny brass keys. He finds 25 more keys hidden inside a dusty old drawer. How many keys does Detective Leo have in total?
CUBES Steps Done:
✓ Circle Numbers ✓ Underline Question ✓ Box Clues ✓ Evaluate
Show Model or Drawing Here:
Part-Part-Whole Model
48 keys
25 keys
Total: ? (73)
48 + 25 = 48 + 20 + 5 = 68 + 5 = 73
Equation:
48 + 25 = 73 (Regrouping: 8 + 5 = 13, 40 + 20 + 10 = 70)
Complete Sentence Answer:
Detective Leo has 73 keys in total.
CASE FILE 02: THE FUGITIVE FOOTPRINTS
Officer Maya spotted 64 mysterious muddy footprints on the garden path. By noon, 38 of those footprints had washed away in the rain. How many footprints are still visible?
CUBES Steps Done:
✓ Circle Numbers ✓ Underline Question ✓ Box Clues ✓ Evaluate
Show Model or Drawing Here:
Tape Diagram / Comparison
[ Total Footprints: 64 ]
Washed away: 38
Left: ? (26)
64 - 38 = (50 - 30) + (14 - 8) = 20 + 6 = 26
Equation:
64 - 38 = 26 (Regrouping: Borrow 1 ten to make 14 ones)
Complete Sentence Answer:
There are 26 footprints still visible.
CLUE CRACKERS WORKSHEET • TEACHER ANSWER KEY PAGE 1 OF 2
ANSWER KEY • SECURE
CLUE CRACKERS
★ TEACHER ANSWER KEY ★ Active Investigations
DETECTIVE: MASTER SOLVER
[ SECURE FILE ]
CASE FILE 03: THE COIN BANDIT
The central bank vault held 92 shining golden coins. A sneaky bandit took some coins, leaving only 54 golden coins left behind. How many coins did the bandit steal?
CUBES Steps Done:
✓ Circle Numbers ✓ Underline Question ✓ Box Clues ✓ Evaluate
Show Model or Drawing Here:
Missing Part Equation
92 (Total) - 38 (Stolen) = 54 (Left)
Or: 92 - 54 = 38
Think: 92 - 50 = 42. Then 42 - 4 = 38.
Equation:
92 - 54 = 38 (Bandit took 38 coins)
Complete Sentence Answer:
The bandit stole 38 golden coins.
CASE FILE 04: SECRET MESSAGES
Agent Maya decoded 37 secret messages on Monday and 45 messages on Tuesday. If she needs to decode 100 messages in total, how many more messages does she have left to decode?
CUBES Steps Done:
✓ Circle Numbers ✓ Underline Question ✓ Box Clues ✓ Evaluate
Show Model or Drawing Here:
Two-Step Investigation
Step 1 (Add): Monday (37) + Tuesday (45) = 82 decoded.
Step 2 (Subtract): Goal (100) - Decoded (82) = 18 left.
Equation:
37 + 45 = 82
100 - 82 = 18
Complete Sentence Answer:
She has 18 more messages left to decode.
CLUE CRACKERS WORKSHEET • TEACHER ANSWER KEY PAGE 2 OF 2
Clue Crackers Slides AGENCY HQ • SESSION 1
MATH DETECTIVE TRAINING
CLUE CRACKERS
Mastering addition and subtraction word problems within 100 using the powerful C.U.B.E.S. Strategy !
TOP SECRET • DETECTIVE NOTEBOOK
SLIDE 1 OF 5
THE CASE-SOLVING METHOD
THE C.U.B.E.S. TOOLBELT
Detective Protocol
C
Circle
Find and circle all numbers and labels.
U
Underline
Underline the question being asked.
B
Box
Box math action words / key clues.
Evaluate
Plan your operation: Add or Subtract ?
Solve & Check
Write equation, solve, and check your work!
MEMORIZE THESE CLUES TO SOLVE ANY CASE
SLIDE 2 OF 5
CASE FILE #01 IN ACTION
THE GOLDEN KEYS
Addition Example
CRIME SCENE TEXT:
Detective Leo has 48 shiny brass keys. He finds 25 more keys hidden inside a dusty old drawer. How many keys does Detective Leo have in total?
E • EVALUATE & PLAN
Keywords more and in total tell us we are combining parts.
Operation: ADDITION (+)
S • SOLVE & CHECK
48 + 25 = 73
Sentence: Detective Leo has 73 keys in total.
NOTICE HOW EACH C.U.B.E.S. ELEMENT IS VISIBLE
SLIDE 3 OF 5
CASE FILE #02 IN ACTION
THE FUGITIVE FOOTPRINTS
Subtraction Example
CRIME SCENE TEXT:
Officer Maya spotted 64 mysterious muddy footprints. By noon, 38 of those footprints had washed away in the rain. How many footprints are still visible?
E • EVALUATE & PLAN
Keywords washed away and still visible tell us parts are being removed.
Operation: SUBTRACTION (-)
S • SOLVE & CHECK
64 - 38 = 26
Sentence: There are 26 footprints still visible.
SUBTRACTION CAN NEED REGROUPING! WATCH YOUR ONES PLACE.
SLIDE 4 OF 5
MISSION ACCOMPLISHED