Double Play Teacher Guide Teacher Case File
Double Play Decoders
Focus: Multi-Step Math Word Problems (Grades 3-5)
Unit: Algebraic Thinking Duration: 60 Minutes
Learning Objectives
Students will be able to dissect complex word problems, identify clue words indicating distinct operations, and solve two-step problems using visual tape diagrams and equations.
Materials Needed
Decoder Anchor Chart
Double Play Slides
Double Trouble Worksheet
Exit Ticket Mini-Cards
Highlighters (2 colors)
Core Strategy
The Double Play Strategy: Break the problem into two distinct acts. Solve Act I first, label the intermediate answer, then use it as a clue to solve Act II.
1 The Hook: Case of the Hidden Number (10 Min)
Write on the board: "Leo had 12 marbles. His sister gave him 5 more. He gave 4 to Sam. How many marbles does Leo have now?"
Prompt: "Why can't we solve this with just one equation? What is the hidden mystery number we need to find first?" Guide students to see that Leo's marble count after his sister gave him more is the "hidden key" needed before we can subtract Sam's marbles.
2 Direct Instruction: Operation Decoding (15 Min)
Display the Decoder Anchor Chart . Introduce the 4-Step Case File Process:
Inspect: Read the entire scenario once. Circle the numbers.Dismantle: Split the problem into Act I and Act II. Underline the target question.Represent: Draw a visual tape diagram or write a variable equation for each act.Solve & Double-Check: Compute the numbers and ask, "Does my response make sense?"
Teacher Script: "Think of yourselves as mathematical detectives. If you try to solve the entire case at once, you will trip over the clues. We must solve the first mystery (Act I) to unlock the tool we need for the second mystery (Act II)."
Double Play Decoders • Teacher Guide Page 1 of 2
Teacher Case File
Double Play Decoders
Focus: Guided Practice & Classroom Intervention
Unit: Algebraic Thinking Duration: 60 Minutes
Suggested Pacing
0-10 min The Hook
10-25 min Direct Instruction
25-40 min Guided Practice
40-55 min Independent Work
55-60 min Exit Ticket
Common Pitfalls
The "One-and-Done" Error: Students solve the first operation and stop, assuming they are finished. Teach them to compare their intermediate answer with the final question to see if it makes sense.
3 Guided Practice: Decoupled Equations (15 Min)
Work through Case #1 as a group. Model how to translate word problems into two distinct parts:
Case #1: The Baker's Delivery
"Mrs. Higgins baked 48 chocolate cupcakes. She threw away 8 burnt ones. She divided the remaining cupcakes equally into boxes of 8. How many boxes did she fill?"
Act I (The Subtraction):
Act II (The Division):
Ask: "What would have happened if we divided 48 by 8 first?" (We would have incorrectly included the burnt cupcakes). Emphasize sequence.
4 Differentiation Strategies
Support (Struggling Learners)
Provide two-color highlighters. Have students highlight information for "Act I" in yellow and "Act II" in pink. Use physical counters to model the "remaining" step.
Extend (Advanced Learners)
Challenge students to write a single equation with parentheses representing the entire multi-step process, e.g., (48 - 8) ÷ 8 = x .
Double Play Decoders • Teacher Guide Page 2 of 2
Decoder Anchor Chart TOP SECRET • CLASSROOM REFERENCE
The Double Play Decoder
Your 4-Step Blueprint to Solve Multi-Step Math Missions
1
Inspect
Read carefully. Circle numbers and clue words.
2
Dismantle
Break into two acts: Act I and Act II.
3
Represent
Draw tape diagrams and write equations.
4
Solve
Compute Act I first, then use it for Act II.
Operation Decoder Dictionary
Addition (+)
Sum, altogether, combined, total, extra, in addition, increased by
Subtraction (-)
Difference, left over, remaining, fewer than, decrease, dropped
Multiplication (×)
Product, times, each (getting more), groups of, double, triple
Division (÷)
Quotient, share equally, cut up, split, groups of (finding count)
Case File #104: The Secret Agent's Gadget Run
Agent J purchased 4 packs of spy pens. Each pack has 6 pens inside. He then gave away 5 pens to Agent M. How many spy pens does Agent J have left over?
ACT I: Find Total Purchased STEP 1
We need the absolute total count of pens before any are given away.
6
6
6
6
4 × 6 = 24 total pens
ACT II: Remove Given Pens STEP 2
Use the total count of 24 pens, then subtract the 5 pens given away.
Left over (19)
Given (5)
24 - 5 = 19 pens left over
Double Play Decoders • Visual Anchor Chart Post in Classroom or Glue in Notebooks
Double Play Practice Worksheet Student Mission File
Operation: Double Trouble
Solve the double-act word problems below. Show all your work for both operations!
Name:
Date:
Mission Rule: Identify Act I (the first operation) and Act II (the second operation) for every case.
Case File #1: The Missing Soccer Balls
Coach Ramirez started the season with 18 soccer balls . He bought 3 new bags of soccer balls, with 6 balls inside each bag . How many total soccer balls does Coach Ramirez have now?
ACT I: Find Total Purchased
ACT II: Combine with Starting Amount
Final Answer: soccer balls
Case File #2: The Sweet Shop Delivery
The Sweet Shop made 45 candy bars . They had to discard 9 broken candy bars . The remaining candy bars were divided equally into 4 gift baskets . How many candy bars were placed in each basket?
ACT I: Subtract Broken Bars
ACT II: Divide into Gift Baskets
Final Answer: candy bars per basket
Double Play Decoders • Student Worksheet Page 1 of 2
Student Mission File
Operation: Double Trouble
Solve the final case files and write your own multi-step case file below.
Name:
Date:
Case File #3: The Comic Book Collector
Maya bought 5 boxes of vintage comic books . Each box contained 8 comics . Her brother then gifted her 12 more comic books . How many comic books does Maya have in total?
ACT I: Solve total in boxes
ACT II: Add brother's gift
Final Answer: comic books
Creative Challenge: Design Your Mission
Draft your own two-step word problem. Be creative! Use any character names and real-world items you like. Ensure it requires two distinct math operations.
ACT I Workspace
ACT II Workspace
My Solution:
Double Play Decoders • Student Worksheet Page 2 of 2
Double Play Exit Ticket Cut Here
Mission Exit Pass
The Code Card Case
Name:
Date:
The Mission: Agent Maya had 35 super-secret code cards . She lost 7 cards on a mission. She split the remaining cards equally among 4 file folders . How many code cards did she put in each folder?
Act I Workspace
Act II Workspace
Self-Rating:
🕵️ I need backup 🚀 Mission solved!
Final Answer: cards
Mission Exit Pass
The Code Card Case
Name:
Date:
The Mission: Agent Maya had 35 super-secret code cards . She lost 7 cards on a mission. She split the remaining cards equally among 4 file folders . How many code cards did she put in each folder?
Act I Workspace
Act II Workspace
Self-Rating:
🕵️ I need backup 🚀 Mission solved!
Final Answer: cards
