Grade 3Reading: grades 3-4AdditionPlace valueRoundingSkip countingDivision
The Case of the Missing Golden Compass
The Golden Compass has disappeared from Cloudcrest Airstation! A sneaky sky bandit took off with it. Use your detective notebook to inspect clues and find out 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 | Airship Gear | Gadget Tool | Glove Hand | Goggle Strap | Fear |
|---|---|---|---|---|---|
| Navigator Eli | Wind Cannon | Map Case | Right Glove On | Blue Strap | Loud Whistles |
| Ranger Noah | Glider Wings | Map Case | Right Glove On | Gold Strap | Bright Lights |
| Officer Ben | Steam Jet | Map Case | Left Glove On | Blue Strap | Strong Gusts |
| Pilot Felix | Grapple Hook | Spyglass | Left Glove On | Gold Strap | Strong Gusts |
| Sky Scout Ava | Rocket Boots | Signal Flare | Right Glove On | Gold Strap | Loud Whistles |
| Scout Mia | Wind Cannon | Brass Key | Right Glove On | Gold Strap | Loud Whistles |
| Captain Zoe | Glider Wings | Map Case | Right Glove On | Gold Strap | Loud Whistles |
| Navigator Owen | Glider Wings | Brass Key | Right Glove On | Blue Strap | Strong Gusts |
| Ranger Kai | Steam Jet | Brass Key | Left Glove On | Red Strap | Loud Whistles |
| Sky Scout Nora | Grapple Hook | Map Case | Left Glove On | Blue Strap | Bright Lights |
| Explorer Maya | Steam Jet | Map Case | Right Glove On | Gold Strap | Bright Lights |
| Scout Iris | Glider Wings | Brass Key | Left Glove On | Red Strap | Bright Lights |
| Pilot Jax | Glider Wings | Brass Key | Right Glove On | Blue Strap | Loud Whistles |
| Officer Ruby | Glider Wings | Compass Dial | Right Glove On | Red Strap | Strong Gusts |
| Pilot Liam | Wind Cannon | Map Case | Right Glove On | Gold Strap | Loud Whistles |
| Captain Milo | Wind Cannon | Signal Flare | Right Glove On | Gold Strap | Loud Whistles |
| Explorer Ella | Grapple Hook | Compass Dial | Left Glove On | Red Strap | Bright Lights |
| Officer Lucas | Steam Jet | Spyglass | Left Glove On | Gold Strap | Loud Whistles |
| Aviation Sam | Grapple Hook | Spyglass | Right Glove On | Red Strap | Strong Gusts |
| Pilot Ezra | Steam Jet | Signal Flare | Left Glove On | Gold Strap | Strong Gusts |
| Navigator Leo | Steam Jet | Spyglass | Left Glove On | Blue Strap | Strong Gusts |
Clue 1
Addition
You tally up the supply crates in the cargo bay to unlock the first clue chest.
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
895
509
905
548
373
340
253
987
T
895
253
919
905
497
340
919
T
895
788
373
858
858
795
373
548
858
373
497
497
619
905
795
350 + 545 =T
633 + 286 =O
247 + 548 =Y
143 + 230 =A
262 + 286 =B
643 + 344 =I
192 + 305 =S
121 + 219 =N
231 + 278 =H
546 + 312 =R
268 + 351 =K
410 + 495 =E
275 + 513 =C
77 + 176 =D
0/14 letters found
Clue 2
Place value
You check the digits on the door lock code to see which number is in the hundreds place.
Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.
W
70
50
40
800
300
90
90
90
5000
W
70
3000
50
9000
900
40
9000
500
100
80
300
100
800
40
900
300
600
5000
800
10
50
40
What is the value of the 7 in 578?W
What is the value of the 1 in 415?D
What is the value of the 5 in 25,384?A
What is the value of the 6 in 9,694?B
What is the value of the 8 in 3,387?V
What is the value of the 3 in 3,254?R
What is the value of the 1 in 156?O
What is the value of the 4 in 841?T
What is the value of the 5 in 6,759?I
What is the value of the 8 in 9,806?N
What is the value of the 9 in 8,955?H
What is the value of the 5 in 6,570?L
What is the value of the 9 in 9,121?G
What is the value of the 3 in 391?E
What is the value of the 9 in 294?S
0/15 letters found
Clue 3
Rounding
The cloud radar screen rounds the airship distance to the nearest hundred to trace the flight.
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
60
500
9000
400
50
600
7000
200
6000
200
7000
700
4000
9000
T
60
500
9000
2000
700
300
300
80
30
T
60
500
70
700
50
200
80
500
30
6000
T
60
70
9000
6000
Round 63 to the nearest tenT
Round 5,840 to the nearest thousandS
Round 490 to the nearest hundredH
Round 8,795 to the nearest thousandE
Round 84 to the nearest tenW
Round 2,373 to the nearest thousandM
Round 6,741 to the nearest thousandR
Round 436 to the nearest hundredG
Round 235 to the nearest hundredD
Round 317 to the nearest hundredF
Round 3,883 to the nearest thousandV
Round 69 to the nearest tenL
Round 674 to the nearest hundredO
Round 30 to the nearest tenI
Round 47 to the nearest tenU
Round 553 to the nearest hundredA
0/16 letters found
Clue 4
Skip counting
You count the rope ladder steps by fours to climb up to the observation deck quickly.
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
22
20
35
36
80
14
16
30
8
26
30
110
16
45
120
9
30
80
26
20
50
6
36
30
14
14
12
39
80
120
39
6
39
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, ___, 24, 26G
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, ___, 39, 42D
Skip-count by 3s. Fill the blank: 3, 6, 9, ___, 15, 18H
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, ___, 40, 45L
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, ___, 42, 45E
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, ___, 50, 55I
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, ___, 120, 130B
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, ___, 130, 140C
Skip-count by 2s. Fill the blank: 2, 4, ___, 8, 10N
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, ___, 28, 30F
Skip-count by 3s. Fill the blank: 3, 6, ___, 12, 15W
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, ___, 90, 100S
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, ___, 18, 20R
Skip-count by 10s. Fill the blank: 10, 20, ___, 40, 50A
Skip-count by 5s. Fill the blank: 5, 10, 15, ___, 25, 30O
Skip-count by 2s. Fill the blank: 2, 4, 6, ___, 10, 12P
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, ___, 16, 18T
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, ___, 55, 60U
0/18 letters found
Clue 5
Division facts (1-12) — the last clue
You divide the fuel canisters equally among the search gliders to power the investigation.
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
40 ÷ 4 = ?
4 ÷ 2 = ?
44 ÷ 4 = ?
44 ÷ 11 = ?
99 ÷ 11 = ?
60 ÷ 12 = ?
48 ÷ 6 = ?
3 ÷ 3 = ?
30 ÷ 5 = ?
15 ÷ 5 = ?
28 ÷ 4 = ?
Step 2 — cross out the sentence with each answer
1.The villain swung down with a grapple hook, then checked the compass dial.
2.The villain blew past with a wind cannon, then tucked away a map case.
3.The villain swung down with a grapple hook, then scouted with a spyglass.
4.The villain blew past with a wind cannon, then checked the compass dial.
5.The villain blasted off with rocket boots, then tucked away a map case.
6.The villain zoomed away on a steam jet, then scouted with a spyglass.
7.The villain zipped across with glider wings, then scouted with a spyglass.
8.The villain blasted off with rocket boots, then dropped a brass key.
9.The villain swung down with a grapple hook, then dropped a brass key.
10.The villain blasted off with rocket boots, then fired a signal flare.
11.The villain zipped across with glider wings, then tucked away a map case.
12.The villain blew past with a wind cannon, then fired a signal flare.
Solve it
Name the culprit
Choose the one suspect left standing.
Answer Key — The Case of the Missing Golden Compass
Culprit: Captain Milo (Wind Cannon · Signal Flare · Right Glove On · Gold Strap · Loud Whistles)
- Clue 1 (Addition): "THE BANDIT DOES NOT CARRY A BRASS KEY"350 + 545 = 895 (T) · 633 + 286 = 919 (O) · 247 + 548 = 795 (Y) · 143 + 230 = 373 (A) · 262 + 286 = 548 (B) · 643 + 344 = 987 (I) · 192 + 305 = 497 (S) · 121 + 219 = 340 (N) · 231 + 278 = 509 (H) · 546 + 312 = 858 (R) · 268 + 351 = 619 (K) · 410 + 495 = 905 (E) · 275 + 513 = 788 (C) · 77 + 176 = 253 (D)
- Clue 2 (Place value): "WITNESS SAW RIGHT GLOVE ON THE BANDIT"What is the value of the 7 in 578? = 70 (W) · What is the value of the 1 in 415? = 10 (D) · What is the value of the 5 in 25,384? = 5000 (A) · What is the value of the 6 in 9,694? = 600 (B) · What is the value of the 8 in 3,387? = 80 (V) · What is the value of the 3 in 3,254? = 3000 (R) · What is the value of the 1 in 156? = 100 (O) · What is the value of the 4 in 841? = 40 (T) · What is the value of the 5 in 6,759? = 50 (I) · What is the value of the 8 in 9,806? = 800 (N) · What is the value of the 9 in 8,955? = 900 (H) · What is the value of the 5 in 6,570? = 500 (L) · What is the value of the 9 in 9,121? = 9000 (G) · What is the value of the 3 in 391? = 300 (E) · What is the value of the 9 in 294? = 90 (S)
- Clue 3 (Rounding): "THE GUARDS DROVE THEM OFF WITH LOUD WHISTLES"Round 63 to the nearest ten = 60 (T) · Round 5,840 to the nearest thousand = 6000 (S) · Round 490 to the nearest hundred = 500 (H) · Round 8,795 to the nearest thousand = 9000 (E) · Round 84 to the nearest ten = 80 (W) · Round 2,373 to the nearest thousand = 2000 (M) · Round 6,741 to the nearest thousand = 7000 (R) · Round 436 to the nearest hundred = 400 (G) · Round 235 to the nearest hundred = 200 (D) · Round 317 to the nearest hundred = 300 (F) · Round 3,883 to the nearest thousand = 4000 (V) · Round 69 to the nearest ten = 70 (L) · Round 674 to the nearest hundred = 700 (O) · Round 30 to the nearest ten = 30 (I) · Round 47 to the nearest ten = 50 (U) · Round 553 to the nearest hundred = 600 (A)
- Clue 4 (Skip counting): "GOLD STRAP FABRIC WAS FOUND AT THE SCENE"Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, ___, 24, 26 = 22 (G) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, ___, 39, 42 = 36 (D) · Skip-count by 3s. Fill the blank: 3, 6, 9, ___, 15, 18 = 12 (H) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, ___, 40, 45 = 35 (L) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, ___, 42, 45 = 39 (E) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, ___, 50, 55 = 45 (I) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, ___, 120, 130 = 110 (B) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, ___, 130, 140 = 120 (C) · Skip-count by 2s. Fill the blank: 2, 4, ___, 8, 10 = 6 (N) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, ___, 28, 30 = 26 (F) · Skip-count by 3s. Fill the blank: 3, 6, ___, 12, 15 = 9 (W) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, ___, 90, 100 = 80 (S) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, ___, 18, 20 = 16 (R) · Skip-count by 10s. Fill the blank: 10, 20, ___, 40, 50 = 30 (A) · Skip-count by 5s. Fill the blank: 5, 10, 15, ___, 25, 30 = 20 (O) · Skip-count by 2s. Fill the blank: 2, 4, 6, ___, 10, 12 = 8 (P) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, ___, 16, 18 = 14 (T) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, ___, 55, 60 = 50 (U)
- Clue 5 (Division facts (1-12)): surviving statement (box 12) → Captain Milo40 ÷ 4 = 10 · 4 ÷ 2 = 2 · 44 ÷ 4 = 11 · 44 ÷ 11 = 4 · 99 ÷ 11 = 9 · 60 ÷ 12 = 5 · 48 ÷ 6 = 8 · 3 ÷ 3 = 1 · 30 ÷ 5 = 6 · 15 ÷ 5 = 3 · 28 ÷ 4 = 7
About this mystery
- Grade level
- Grade 3 math
- Math topics
- Addition, Place value, Rounding, Skip counting, Division
- Reading level
- grades 3-4
- Theme
- The Case of the Missing Golden Compass — set in Cloudcrest Airstation
- Format
- Interactive online & printable worksheet with answer key
- Solution
- One unique, verified culprit among 21 suspects