Clue Words Presentation CODE BREAKERS MISSION 01
MATH LAB SECURE
TARGET: WORDS TO SYMBOLS & UNKNOWN NUMBERS
Decoding Clue Words & Mystery Boxes
Discover how real mathematicians translate everyday words into secret algebraic symbols and find hidden numbers.
Code 1
More / Add
-
Code 2
Fewer / Subtract
?
Code 3
Box / Variable
OPERATION DECODER Matching Everyday Words to Math
Add (+) Clue Words
Means putting items together or getting more.
"4 more than a number"
→ n + 4
"Total of 5 and 3"
→ 5 + 3
Subtract (-) Clue Words
-
Means taking away, losing, or comparing difference.
"2 fewer than a number"
→ n - 2
"Start with 7, take away 3"
→ 7 - 3
Pro Detective Tip: The letter n or x stands for our mysterious unknown number! KEY SKILL
FIND THE UNKNOWN What is hiding inside the box?
CASE A: ADDITION
4 +
?
= 9
Think: "I have 4 dots. How many more dots make 9?"
Count up from 4 to 9: 5, 6, 7, 8, 9 (5 dots!)
□ = 5
CASE B: LETTER VARIABLE
b - 3 = 5
Think: "What number can lose 3 and still have 5 left?"
Put 5 and 3 back together: 5 + 3 = 8
b = 8
A letter like b is just a box with a name!
TEAM CODE CHECK Solve with your mission partner
Challenge 1
Translate: "6 more than a number n"
n + 6
Challenge 2
Find the mystery box: 7 + □ = 10
□ = 3
Challenge 3
Find the unknown letter: x - 4 = 2
x = 6
Ready for individual mission work? Grab your pencil and decoder worksheet! ✓ All Systems Ready
Clue Words Practice Worksheet Code Breakers // Lesson 1
Match Words to Symbols
Name:
Date: Period:
Examples (Read These First)
Example 1: "3 more than a number n"
Short Explanation: "More than" means add (+). We start with n and add 3.
Expression: n + 3
Example 2: "2 fewer than a number n"
Short Explanation: "Fewer than" means subtract (-). Start with n and take away 2.
Expression: n - 2
Your Turn • Part 1: Match Each Phrase to its Expression
1. 5 more than a number n
2. 4 fewer than a number n
3. A number n increased by 6
4. Take away 1 from a number n
A. n - 4 Choice A
B. n + 5 Choice B
C. n - 1 Choice C
D. n + 6 Choice D
Your Turn • Part 2: Write the Expression (Use the letter x)
5. "8 more than a number"
Expression:
6. "3 fewer than a number"
Expression:
7. "The sum of a number and 7"
Expression:
8. "Take away 5 from a number"
Expression:
Code Breakers Math // Lesson 1 Practice Turn page for Find the Unknown → Page 1 of 2
Code Breakers // Lesson 1
Find the Unknown Number
Target: Addition & Subtraction to 15
Examples (Read These First)
Example 1: 4 + □ = 7
Short Explanation: Start at 4. Count up to 7 on fingers or dots: 5, 6, 7 (3 dots counted).
Mystery Box: □ = 3
Example 2: y - 2 = 6
Short Explanation: The letter y is just a box. Put 6 and 2 back together: 6 + 2 = 8.
Variable Letter: y = 8
Your Turn • Part 3: Find the Number in the Box
9. 5 + □ = 9 Count up from 5 to 9
□ =
10. 7 + □ = 11 Count up from 7 to 11
□ =
11. 8 - □ = 5 Count back from 8 to 5
□ =
12. □ - 3 = 4 Add 4 and 3 together
□ =
Your Turn • Part 4: Find the Secret Letter Value
13. n + 4 = 10 What + 4 equals 10?
n =
14. x + 6 = 9 What + 6 equals 9?
x =
15. y - 4 = 3 Put 3 and 4 together
y =
16. k - 2 = 7 Put 7 and 2 together
k =
Code Breakers Math // Lesson 1 Practice Completed Practice Checked ✓ Page 2 of 2
Clue Words Facilitation Guide Teacher Guide // Lesson 1
Clue Words & Unknowns Guide
Pacing: 45 Minutes
Instructional Focus: Algebraic Foundations
Accessible computation ensures student cognitive energy focuses entirely on algebraic structure . All calculations remain strictly within 15. The "Code Breaker" theme treats variables as secret placeholders, building confidence with mathematical symbols.
Lesson Pacing Breakdown
10 Min
Model Examples 1 & 2: Review clue words on the board. Emphasize that "more than" means + and "fewer than" means -. Teach students to write the variable first.
15 Min
Guided Mystery Box Decoding: Show that □ and n are identical. Model counting up from 4 to 7 using dot counters or fingers.
15 Min
Independent Student Practice: Back off and allow students to complete Parts 1–4 independently on their clean worksheet pages.
5 Min
Check & Wrap Up: Have students self-check their answers against the board to verify mastery before moving to Lesson 2.
Common Misconception Alert: Subtraction Order
When translating "3 fewer than a number" , students frequently write 3 - x. Remind them: "You have your pocket money (x) first, then you lose 3 dollars. Always write x - 3."
Code Breakers Math // Lesson 1 Teacher Guide See Page 2 for Worked Solutions → Page 1 of 2
Teacher Guide // Lesson 1
Complete Worked Answer Key
Official Solutions
Worksheet Page 1 Solutions
Part 1: Matching
1. 5 more than n → B (n + 5)
2. 4 fewer than n → A (n - 4)
3. n increased by 6 → D (n + 6)
4. Take away 1 from n → C (n - 1)
Part 2: Writing Expressions
5. 8 more than a number → x + 8
6. 3 fewer than a number → x - 3
7. Sum of a number and 7 → x + 7
8. Take away 5 from a number → x - 5
Worksheet Page 2 Solutions
Part 3: Mystery Boxes
9. 5 + □ = 9 → □ = 4 (count 6,7,8,9)
10. 7 + □ = 11 → □ = 4 (count 8,9,10,11)
11. 8 - □ = 5 → □ = 3 (8 - 5 = 3)
12. □ - 3 = 4 → □ = 7 (4 + 3 = 7)
Part 4: Variable Letters
13. n + 4 = 10 → n = 6
14. x + 6 = 9 → x = 3
15. y - 4 = 3 → y = 7
16. k - 2 = 7 → k = 9
Quick Check Assessment Rubric
14–16 Correct
Ready for Substitution in Lesson 2
11–13 Correct
Secret Swap Presentation CODE BREAKERS MISSION 02
MATH LAB SECURE
TARGET: EVALUATING WITH SUBSTITUTION
The Secret Number Swap
Learn the core superpower of algebra: swapping out a letter variable for a real number to unlock the final answer.
⇆
Step 1: The Swap
Replace the letter with a number
=
Step 2: Calculate
Add or subtract to solve
SUBSTITUTION PROTOCOL How to evaluate an expression
ACTION 01 👁
Read the Secret Value
The mission briefing tells you what the letter equals.
Given Clue: x = 5
ACTION 02 ✏️
Swap & Calculate
Erase the letter, drop in the number, and add!
Expression: x + 4
Swap: 5 + 4
Answer = 9
REMEMBER: "Evaluating" just means finding the final number value!
SUBTRACTION SWAP LAB Keeping the order straight
MISSION: SUBTRACTION
Clue Value: m = 8
Expression: m - 3
Swap m for 8: 8 - 3
Result: 5
MISSION: NUMBER FIRST
Clue Value: k = 4
Expression: 10 - k
Swap k for 4: 10 - 4
Result: 6
Count back on your fingers or cross off dots to check your subtraction!
CRACK THE SAFE Combine all 3 answers to unlock
MASTER CLUE: x = 3
DIAL 1
x + 7
3 + 7 =
10
DIAL 2
9 - x
9 - 3 =
6
DIAL 3
x + x
3 + 3 =
6
The Safe Combination Code is: 10 - 6 - 6 🔓 VAULT OPEN
Secret Swap Practice Worksheet Code Breakers // Lesson 2
Evaluate with Substitution: Addition
Name:
Date: Period:
Examples (Read These First)
Example 1: Evaluate x + 5 if x = 4
Short Explanation: Replace the letter x with the number 4. Then add: 4 + 5 = 9.
Work: 4 + 5 = 9
Example 2: Evaluate 6 + b if b = 3
Short Explanation: Keep the 6 first. Replace the letter b with 3. Then add: 6 + 3 = 9.
Work: 6 + 3 = 9
Your Turn • Substitute the Number and Add
1. Evaluate: a + 4 Given: a = 3
Write the number swap: _____ + 4
Answer:
2. Evaluate: m + 7 Given: m = 2
Write the number swap: _____ + 7
Answer:
3. Evaluate: 5 + c Given: c = 5
Write the number swap: 5 + _____
Answer:
4. Evaluate: 8 + p Given: p = 4
Write the number swap: 8 + _____
Answer:
5. Evaluate: y + 6 Given: y = 6
Write the number swap: _____ + 6
Answer:
6. Evaluate: k + k Given: k = 4
Swap both letters: _____ + _____
Answer:
Code Breakers Math // Lesson 2 Practice Turn page for Subtraction Substitution → Page 1 of 2
Code Breakers // Lesson 2
Evaluate with Substitution: Subtraction
Target: Subtract within 15
Examples (Read These First)
Example 1: Evaluate x - 3 if x = 8
Short Explanation: Replace x with 8. Keep the minus sign. Then subtract: 8 - 3 = 5.
Work: 8 - 3 = 5
Example 2: Evaluate 10 - y if y = 4
Short Explanation: Keep 10 at the front. Replace y with 4. Subtract: 10 - 4 = 6.
Work: 10 - 4 = 6
Your Turn • Substitute the Number and Subtract
7. Evaluate: x - 5 Given: x = 9
Write the number swap: _____ - 5
Answer:
8. Evaluate: m - 2 Given: m = 7
Write the number swap: _____ - 2
Answer:
9. Evaluate: 10 - n Given: n = 3
Write the number swap: 10 - _____
Answer:
10. Evaluate: 12 - b Given: b = 4
Write the number swap: 12 - _____
Answer:
11. Evaluate: p - 6 Given: p = 8
Write the number swap: _____ - 6
Answer:
Secret Swap Facilitation Guide Teacher Guide // Lesson 2
Secret Swap Facilitation Guide
Pacing: 45 Minutes
Instructional Focus: Demystifying Variable Substitution
Evaluating algebraic expressions simply means "swap the letter for a given number, then calculate the answer." For students with 2nd-grade arithmetic foundations, having only 1–2 examples with short explanations allows them to see the exact pattern without reading fatigue, leaving ample focus for independent practice.
Tactile Intervention: The Sticky-Note Cover Technique
If a student pauses when seeing x + 4 with x = 3, give them a small sticky note:
Have the student write the number 3 on the sticky note.
Place the sticky note directly over the letter x on their worksheet.
Read the expression out loud as pure arithmetic: "3 + 4 = 7."
Lesson Flow
10 Min
Direct Instruction: Model the two examples at the top of Page 1. Emphasize that evaluating ends with one single number.
25 Min
Independent Practice: Students complete Problems 1–6 (Addition) and Problems 7–12 (Subtraction). Circulate to support subtraction directionality.
10 Min
Debrief & Review: Review Problem 6 (k + k) and Problem 9 (10 - n) as key milestone checks.
Code Breakers Math // Lesson 2 Teacher Guide See Page 2 for Worked Solutions → Page 1 of 2
Teacher Guide // Lesson 2
Complete Worked Answer Key
Official Solutions
Worksheet Page 1: Addition Swaps
1. a + 4 (where a = 3)
Swap: 3 + 4 = 7
2. m + 7 (where m = 2)
Swap: 2 + 7 = 9
3. 5 + c (where c = 5)
Swap: 5 + 5 = 10
4. 8 + p (where p = 4)
Swap: 8 + 4 = 12
5. y + 6 (where y = 6)
Swap: 6 + 6 = 12
6. k + k (where k = 4)
Swap: 4 + 4 = 8
Worksheet Page 2: Subtraction Swaps
7. x - 5 (where x = 9)
Swap: 9 - 5 = 4
8. m - 2 (where m = 7)
Swap: 7 - 2 = 5
9. 10 - n (where n = 3)
Swap: 10 - 3 = 7
10. 12 - b (where b = 4)
Swap: 12 - 4 = 8
11. p - 6 (where p = 8)
Swap: 8 - 6 = 2
12. 9 - c (where c = 7)
Swap: 9 - 7 = 2
Observation Check During Work
If a student solves Problem 9 (10 - n with n = 3) as 13, they accidentally added. Have them trace the minus sign with their finger and count down:
Equal Groups Presentation CODE BREAKERS MISSION 03
MATH LAB SECURE
TARGET: COUNT & COMBINE EQUAL GROUPS
Equal Group Quest
Discover how grouping items together creates fast multiplication expressions like 3 × b and unlocks algebraic totals.
▦
Pattern 1
Equal Bags
Pattern 2
Repeated Addition
×
Pattern 3
Algebraic Expression
THE GROUPING BRIDGE From Pictures to Repeated Addition to Algebra
1. PICTURE
4 security bags with 2 gems in each bag:
Bag 1 ● ●
Bag 2 ● ●
Bag 3 ● ●
Bag 4 ● ●
4 equal groups of 2
2. REPEATED ADDITION
Add the amount in each bag together:
2 + 2 + 2 + 2
Total = 8
Skip count: 2, 4, 6, 8
3. ALGEBRA CODE
Write as groups times the items inside:
4 bags of b
4 × b
or simply 4b
Number of groups × Secret amount
Equal groups are just fast addition written in algebra code!
VAULT DECODER LAB Find the total when the bag value is revealed
CASE A: 3 BAGS
Expression: 3 × c
Secret Clue: Each bag holds c = 3 coins.
Repeated Addition: 3 + 3 + 3
Total Coins: 9
CASE B: 2 BOXES
Expression: 2 × k
Secret Clue: Each box holds k = 5 cards.
Repeated Addition: 5 + 5
Total Cards: 10
Notice how 5 + 5 is a doubles fact you already know from 2nd grade!
GROUP SHOWDOWN Can your team decode these 3 vault locks?
Vault Lock 1
5 groups of 2 tokens each
2 + 2 + 2 + 2 + 2 = 10
Vault Lock 2
Write the algebra code for "3 groups of y"
3 × y (or 3y)
Vault Lock 3
Evaluate 3 × y if y = 4
4 + 4 + 4 = 12
You have cracked all 3 missions of Code Breakers Squad! 🏆 MISSION COMPLETE
Equal Groups Practice Worksheet Code Breakers // Lesson 3
Equal Groups and Repeated Addition
Name:
Date: Period:
Examples (Read These First)
Example 1: 3 Bags of 2 Stars
★ ★ ★ ★ ★ ★
Short Explanation: Add 2 three times: 2 + 2 + 2 = 6.
Total = 6 stars
Example 2: 2 Boxes of 5 Coins
● ● ● ● ● ● ● ● ● ●
Short Explanation: Add 5 two times: 5 + 5 = 10.
Total = 10 coins
Your Turn • Count the Equal Groups and Write the Total
1. 4 bags of 2 dots 4 groups
● ● ● ● ● ● ● ●
Repeated Addition: 2 + 2 + 2 + 2 =
Total:
2. 3 boxes of 3 stars 3 groups
★ ★ ★ ★ ★ ★ ★ ★ ★
Repeated Addition: 3 + 3 + 3 =
Total:
3. 2 trays of 6 tokens 2 groups
●●●●●● ●●●●●●
Repeated Addition: 6 + 6 =
Total:
4. 5 packs of 2 cards 5 groups
▦▦ ▦▦ ▦▦ ▦▦ ▦▦
Skip-count by 2s: 2, 4, 6, 8, ___
Total:
Code Breakers Math // Lesson 3 Practice Turn page for Algebraic Group Expressions → Page 1 of 2
Code Breakers // Lesson 3
Algebraic Group Expressions
Target: Groups × Secret Value
Examples (Read These First)
Example 1: 3 Bags with b items
Short Explanation: 3 bags times b items equals 3 × b.
Expression: 3 × b
Example 2: Evaluate if b = 4
Short Explanation: Put 4 in each of the 3 bags: 4 + 4 + 4 = 12.
Total: 12 items
Your Turn • Write the Group Expression and Find the Total
5. You have 4 bags. Each bag has n marbles.
A. Write the group expression: _____ × _____
B. If each bag holds n = 2 marbles, add: 2 + 2 + 2 + 2 =
Total Marbles
6. You have 3 boxes. Each box has x badges.
A. Write the group expression: _____ × _____
B. If each box holds x = 3 badges, add: 3 + 3 + 3 =
Total Badges
7. You have 2 packs. Each pack has k stickers.
A. Write the group expression: _____ × _____
B. If each pack holds k = 5 stickers, add: 5 + 5 =
Total Stickers
8. You have 5 envelopes. Each has y stamps.
A. Write the group expression: _____ × _____
B. If each envelope holds y = 2 stamps, count by 2s: 2, 4, 6, 8, 10
Equal Groups Facilitation Guide Teacher Guide // Lesson 3
Equal Groups Facilitation Guide
Pacing: 45 Minutes
Instructional Focus: Connecting Groups to Algebraic Terms
In 2nd grade, multiplication begins as equal groups and repeated addition (e.g. 2 + 2 + 2). In 6th grade, this represents the foundation of algebraic terms: 3 × b represents 3 groups of whatever amount is inside b. By modeling only 1–2 examples and then backing off, students build independent confidence.
Hands-On Manipulative Strategy: "Cups & Counters"
Place small paper cups on student desks:
Cups = Groups: 3 cups means 3 groups.Inside the Cup = Variable: Until we look inside, the amount is mystery b (written as 3 × b).Revealing Value: When told b = 2, put 2 counters in each cup: 2 + 2 + 2 = 6.
Lesson Flow
10 Min
Direct Instruction: Model Examples 1 & 2 at top of Page 1. Show skip-counting paths (2, 4, 6, 8, 10).
25 Min
Independent Student Work: Back off and let students complete Page 1 (Problems 1–4) and Page 2 (Problems 5–8).
10 Min
Sequence Wrap-Up: Celebrate completing all 3 Code Breakers missions. Connect equal groups to middle school math.
Code Breakers Math // Lesson 3 Teacher Guide See Page 2 for Worked Solutions → Page 1 of 2
Teacher Guide // Lesson 3
Complete Worked Answer Key
Official Solutions
Worksheet Page 1: Equal Groups
1. 4 bags of 2 dots
2 + 2 + 2 + 2 = 8 dots
2. 3 boxes of 3 stars
3 + 3 + 3 = 9 stars
3. 2 trays of 6 tokens
6 + 6 = 12 tokens
4. 5 packs of 2 cards
2, 4, 6, 8, 10 = 10 cards
Worksheet Page 2: Group Expressions
5. 4 bags of n marbles (n = 2)
Expression: 4 × n
Total: 2 + 2 + 2 + 2 = 8 marbles
6. 3 boxes of x badges (x = 3)
Expression: 3 × x
Total: 3 + 3 + 3 = 9 badges
7. 2 packs of k stickers (k = 5)
Expression: 2 × k
Total: 5 + 5 = 10 stickers
8. 5 envelopes of y stamps (y = 2)
Expression: 5 × y
Total: 2, 4, 6, 8, 10 = 10 stamps
Unit Mastery Summary
Lesson 1 Words to symbols & mystery boxes within 15.
Lesson 2 Substitution for addition and subtraction.
Lesson 3 Equal groups, repeated addition & group expressions.
