🏴☠️ PiratesGrade 3Reading: grades 3-4Place valueAdditionSubtractionRoundingMissing addends
The Case of the Golden Compass
The Golden Compass has been stolen from the governor's grand cabin! Only a clever cabin boy or girl can track the clues, solve the ship logs, and find the sneaky pirate who took it.
Suspects
Possible suspects
Cross off a row as each clue rules it out. On screen, tap a row.
21 of 21 still in play
| Name | Primary Skill | Secondary Skill | Writing Hand | Hair Style | Main Fear |
|---|---|---|---|---|---|
| Cutlass Carla | cannon fire | gold digging | writes left handed | curly red hair | hates loud music |
| Sea Dog Sally | sword play | plank walking | writes right handed | curly red hair | hates loud music |
| Sharkbait Sam | map reading | gold digging | writes right handed | braided black beard | hates loud music |
| Calico Jack | map reading | gold digging | writes left handed | braided black beard | allergic to citrus |
| Grace O Malley | map reading | parrot training | writes left handed | messy gray hair | hates loud music |
| William Kidd | cannon fire | sail patching | writes left handed | messy gray hair | hates loud music |
| Quartermaster Quincy | cannon fire | gold digging | writes left handed | messy gray hair | hates loud music |
| Mary Read | anchor tossing | sail patching | writes left handed | braided black beard | allergic to citrus |
| Blackbeard | cannon fire | parrot training | writes right handed | braided black beard | allergic to citrus |
| Long John Silver | cannon fire | plank walking | writes left handed | messy gray hair | scared of sharks |
| Francis Drake | anchor tossing | sail patching | writes left handed | braided black beard | hates loud music |
| Anne Bonny | map reading | gold digging | writes left handed | messy gray hair | hates loud music |
| Doubloon Dan | sword play | sail patching | writes right handed | curly red hair | allergic to citrus |
| Captain Hook | anchor tossing | plank walking | writes left handed | curly red hair | allergic to citrus |
| Cannonball Kate | map reading | sail patching | writes left handed | curly red hair | allergic to citrus |
| Salty Sarah | map reading | parrot training | writes right handed | messy gray hair | hates loud music |
| Crow Nest Ned | sword play | plank walking | writes left handed | braided black beard | scared of sharks |
| Scurvy Steve | anchor tossing | parrot training | writes left handed | messy gray hair | hates loud music |
| Compass Cora | cannon fire | sail patching | writes right handed | braided black beard | scared of sharks |
| Rigging Rusty | map reading | gold digging | writes left handed | braided black beard | hates loud music |
| Henry Morgan | anchor tossing | gold digging | writes left handed | messy gray hair | allergic to citrus |
Clue 1
Place value
We found a torn page from the pirate's ledger. The numbers are written in hundreds, tens, and ones columns. Figure out the total value of each line to reveal the first secret!
Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.
T
90
9000
300
T
90
9000
4000
300
30
6000
5000
300
600
200
5000
T
90
60
2000
T
90
500
9000
600
2000
4000
400
600
What is the value of the 9 in 3,393?T
What is the value of the 2 in 72,703?A
What is the value of the 6 in 6,970?D
What is the value of the 6 in 5,679?S
What is the value of the 5 in 35,367?O
What is the value of the 6 in 9,269?P
What is the value of the 3 in 307?E
What is the value of the 4 in 470?L
What is the value of the 9 in 49,618?H
What is the value of the 4 in 4,683?I
What is the value of the 2 in 8,288?N
What is the value of the 5 in 9,582?C
What is the value of the 3 in 1,537?F
0/13 letters found
Clue 2
Addition
The deckhands are counting the heavy iron cannonballs left on the deck. Add all the piles together to find the true total and unlock this next lead.
Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.
L
202
561
370
973
668
544
808
988
561
988
865
808
578
908
573
342
988
289
561
908
423
808
973
668
561
988
561
501
578
139 + 63 =L
158 + 184 =U
298 + 275 =M
255 + 413 =H
327 + 234 =E
255 + 168 =O
318 + 490 =N
438 + 427 =I
626 + 282 =S
272 + 229 =C
138 + 232 =F
221 + 357 =K
523 + 450 =T
200 + 89 =G
292 + 252 =A
591 + 397 =D
0/16 letters found
Clue 3
Subtraction
The ship's cook says some sea biscuits are missing from the barrel. Take away the eaten biscuits from the starting batch to see what remains!
Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.
T
251
479
692
821
300
732
410
692
726
692
712
T
251
479
692
776
726
692
374
726
427
374
T
251
T
251
479
692
181
776
792
298 - 47 =T
1028 - 296 =O
847 - 121 =R
717 - 5 =D
834 - 13 =Y
774 - 400 =A
400 - 219 =J
433 - 133 =C
1088 - 312 =I
977 - 285 =E
641 - 231 =V
755 - 276 =H
819 - 27 =G
463 - 36 =S
0/14 letters found
Clue 4
Rounding
The captain's brass spyglass dial only works in rounded numbers. Round the distance of the spotted sail to the nearest ten to focus the lens and read the message.
Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.
G
500
90
50
800
600
50
30
90
3000
50
2000
400
8000
9000
40
5000
900
40
600
8000
90
30
G
500
G
500
30
900
G
500
Round 484 to the nearest hundredG
Round 7,515 to the nearest thousandE
Round 3,333 to the nearest thousandW
Round 8,636 to the nearest thousandF
Round 399 to the nearest hundredL
Round 40 to the nearest tenT
Round 2,215 to the nearest thousandS
Round 4,948 to the nearest thousandO
Round 26 to the nearest tenI
Round 46 to the nearest tenA
Round 875 to the nearest hundredN
Round 92 to the nearest tenR
Round 833 to the nearest hundredY
Round 630 to the nearest hundredH
0/14 letters found
Clue 5
Missing addends — the last clue
We have a crate that needs to hold a specific number of gold doubloons, but it is not full. Calculate how many more doubloons we must add to reach the total.
First solve each problem. Then find each answer in the list below and cross that sentence out. One sentence will be left — that's exactly what the villain did!
Step 1 — solve these
10 + ___ = 12
8 + ___ = 18
8 + ___ = 12
1 + ___ = 2
7 + ___ = 14
2 + ___ = 13
2 + ___ = 7
10 + ___ = 22
5 + ___ = 11
5 + ___ = 14
5 + ___ = 8
Step 2 — cross out the sentence with each answer
1.The villain steers the massive ship, then sends a parrot helper.
2.The villain steals the secret map, then digs up a buried chest.
3.The villain draws a shiny sword, then digs up a buried chest.
4.The villain steals the secret map, then sends a parrot helper.
5.The villain fires the loud cannon, then forces a captive to walk the plank.
6.The villain steers the massive ship, then swings away on a rope.
7.The villain fires the loud cannon, then sends a parrot helper.
8.The villain fires the loud cannon, then digs up a buried chest.
9.The villain draws a shiny sword, then sews a hole in the sail.
10.The villain drops the heavy anchor, then sends a parrot helper.
11.The villain steers the massive ship, then forces a captive to walk the plank.
12.The villain draws a shiny sword, then swings away on a rope.
Solve it
Name the culprit
Choose the one suspect left standing.
Answer Key — The Case of the Golden Compass
Culprit: Quartermaster Quincy (cannon fire · gold digging · writes left handed · messy gray hair · hates loud music)
- Clue 1 (Place value): "THE THIEF DOES NOT PATCH SAILS"What is the value of the 9 in 3,393? = 90 (T) · What is the value of the 2 in 72,703? = 2000 (A) · What is the value of the 6 in 6,970? = 6000 (D) · What is the value of the 6 in 5,679? = 600 (S) · What is the value of the 5 in 35,367? = 5000 (O) · What is the value of the 6 in 9,269? = 60 (P) · What is the value of the 3 in 307? = 300 (E) · What is the value of the 4 in 470? = 400 (L) · What is the value of the 9 in 49,618? = 9000 (H) · What is the value of the 4 in 4,683? = 4000 (I) · What is the value of the 2 in 8,288? = 200 (N) · What is the value of the 5 in 9,582? = 500 (C) · What is the value of the 3 in 1,537? = 30 (F)
- Clue 2 (Addition): "LEFT HANDED INK SMUDGES ON THE DECK"139 + 63 = 202 (L) · 158 + 184 = 342 (U) · 298 + 275 = 573 (M) · 255 + 413 = 668 (H) · 327 + 234 = 561 (E) · 255 + 168 = 423 (O) · 318 + 490 = 808 (N) · 438 + 427 = 865 (I) · 626 + 282 = 908 (S) · 272 + 229 = 501 (C) · 138 + 232 = 370 (F) · 221 + 357 = 578 (K) · 523 + 450 = 973 (T) · 200 + 89 = 289 (G) · 292 + 252 = 544 (A) · 591 + 397 = 988 (D)
- Clue 3 (Subtraction): "THEY COVERED THEIR EARS AT THE JIG"298 - 47 = 251 (T) · 1028 - 296 = 732 (O) · 847 - 121 = 726 (R) · 717 - 5 = 712 (D) · 834 - 13 = 821 (Y) · 774 - 400 = 374 (A) · 400 - 219 = 181 (J) · 433 - 133 = 300 (C) · 1088 - 312 = 776 (I) · 977 - 285 = 692 (E) · 641 - 231 = 410 (V) · 755 - 276 = 479 (H) · 819 - 27 = 792 (G) · 463 - 36 = 427 (S)
- Clue 4 (Rounding): "GRAY HAIR WAS LEFT ON THE RIGGING"Round 484 to the nearest hundred = 500 (G) · Round 7,515 to the nearest thousand = 8000 (E) · Round 3,333 to the nearest thousand = 3000 (W) · Round 8,636 to the nearest thousand = 9000 (F) · Round 399 to the nearest hundred = 400 (L) · Round 40 to the nearest ten = 40 (T) · Round 2,215 to the nearest thousand = 2000 (S) · Round 4,948 to the nearest thousand = 5000 (O) · Round 26 to the nearest ten = 30 (I) · Round 46 to the nearest ten = 50 (A) · Round 875 to the nearest hundred = 900 (N) · Round 92 to the nearest ten = 90 (R) · Round 833 to the nearest hundred = 800 (Y) · Round 630 to the nearest hundred = 600 (H)
- Clue 5 (Missing addends): surviving statement (box 8) → Quartermaster Quincy10 + ___ = 12 = 2 · 8 + ___ = 18 = 10 · 8 + ___ = 12 = 4 · 1 + ___ = 2 = 1 · 7 + ___ = 14 = 7 · 2 + ___ = 13 = 11 · 2 + ___ = 7 = 5 · 10 + ___ = 22 = 12 · 5 + ___ = 11 = 6 · 5 + ___ = 14 = 9 · 5 + ___ = 8 = 3
About this mystery
- Grade level
- Grade 3 math
- Math topics
- Place value, Addition, Subtraction, Rounding, Missing addends
- Reading level
- grades 3-4
- Theme
- The Case of the Golden Compass — set in Scurvy Cove, a secret island hidden behind foggy rocks and coral reefs
- Format
- Interactive online & printable worksheet with answer key
- Solution
- One unique, verified culprit among 21 suspects