Grade 4Reading: grades 3-4MultiplicationAdditionSkip countingRoundingMissing addends
The Mystery of Cloud Archipelago
The golden star globe has vanished from the high floating dock! Someone snuck into the flight deck while the Cloud Explorers were away.
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 | Special Gadget | Carried Item | Dominant Hand | Headgear | Secret Weakness |
|---|---|---|---|---|---|
| Tracker May | Jet Boots | Signal Flare | Right-handed | Blue Cap | Loud Whistles |
| Pilot Felix | Grappling Hook | Map Pouch | Left-handed | Red Scarf | Loud Whistles |
| Sailor Tessa | Jet Boots | Brass Spyglass | Left-handed | Green Bandana | Loud Whistles |
| Tracker Nina | Jet Boots | Map Pouch | Right-handed | Blue Cap | Loud Whistles |
| Lookout Maya | Smoke Bombs | Compass Badge | Right-handed | Blue Cap | Loud Whistles |
| Aviator Pip | Grappling Hook | Brass Spyglass | Right-handed | Blue Cap | Loud Whistles |
| Captain Vera | Wind Whistle | Map Pouch | Right-handed | Blue Cap | Fresh Lemonade |
| Lookout Nora | Wind Whistle | Brass Spyglass | Right-handed | Red Scarf | Fresh Lemonade |
| Sky Captain Jack | Grappling Hook | Map Pouch | Right-handed | Green Bandana | Fresh Lemonade |
| Explorer Finn | Wind Whistle | Map Pouch | Right-handed | Red Scarf | Fresh Lemonade |
| Sailor Ruby | Glider Wings | Brass Spyglass | Right-handed | Blue Cap | Loud Whistles |
| Explorer Sam | Jet Boots | Bronze Whistle | Left-handed | Blue Cap | Loud Whistles |
| Captain Cleo | Grappling Hook | Map Pouch | Left-handed | Blue Cap | Bright Flashlights |
| Navigator Rita | Grappling Hook | Map Pouch | Left-handed | Red Scarf | Fresh Lemonade |
| Pilot Bruno | Jet Boots | Bronze Whistle | Left-handed | Green Bandana | Loud Whistles |
| Captain Barnaby | Smoke Bombs | Bronze Whistle | Left-handed | Green Bandana | Bright Flashlights |
| Navigator Iris | Jet Boots | Signal Flare | Right-handed | Red Scarf | Fresh Lemonade |
| Scout Penny | Grappling Hook | Bronze Whistle | Right-handed | Green Bandana | Loud Whistles |
| Flyer Daisy | Smoke Bombs | Signal Flare | Right-handed | Blue Cap | Fresh Lemonade |
| Flyer Gus | Glider Wings | Bronze Whistle | Right-handed | Red Scarf | Bright Flashlights |
| First Mate Leo | Jet Boots | Compass Badge | Left-handed | Red Scarf | Loud Whistles |
Clue 1
Multiplication facts (1-12)
You inspect four supply crates, each packed with neat rows of airship gear.
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
120
25
54
14
21
45
45
24
21
16
77
49
54
35
16
49
T
120
4
24
18
18
1
24
110
24
60
60
49
27
4
25
12 × 10 =T
4 × 1 =C
5 × 5 =H
9 × 3 =U
7 × 5 =S
7 × 7 =O
9 × 2 =R
7 × 3 =I
10 × 11 =M
6 × 9 =E
2 × 8 =N
2 × 7 =V
5 × 9 =L
1 × 1 =Y
11 × 7 =D
12 × 2 =A
5 × 12 =P
0/17 letters found
Clue 2
Addition
You tally up all the brass compasses found inside the control tower.
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
5052
6673
9253
4971
4389
9651
9651
9651
6935
W
5052
4116
6673
9334
6967
9253
6967
6935
4971
2714
4389
2714
9334
4116
6673
9736
7781
4971
4116
7781
9736
4389
3144 + 1908 =W
3496 + 6240 =P
2755 + 3918 =I
1841 + 2548 =E
3062 + 4719 =O
4620 + 2315 =A
6066 + 3585 =S
3020 + 6233 =T
1949 + 3022 =N
4311 + 5023 =G
2390 + 1726 =R
1533 + 1181 =D
2345 + 4622 =H
0/13 letters found
Clue 3
Skip counting
You follow the muddy boot prints spaced out in steady steps along the dock.
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
39
130
26
60
27
55
55
22
27
8
28
22
8
45
28
100
24
55
100
35
90
15
130
27
50
T
39
55
26
50
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, ___, 42, 45T
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, ___, 24, 26A
Skip-count by 2s. Fill the blank: 2, 4, 6, ___, 10, 12N
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, ___, 140, 150H
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, ___, 60, 65L
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, ___, 30, 33I
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, ___, 28, 30E
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, ___, 110, 120O
Skip-count by 5s. Fill the blank: 5, 10, ___, 20, 25W
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, ___, 27, 30M
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, ___, 60, 70S
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, ___, 40, 45U
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, ___, 50, 55F
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, ___, 30, 32R
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, ___, 65, 70V
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, ___, 100, 110D
0/16 letters found
Clue 4
Rounding
The cloud radar screen only shows whole rounded distances for nearby flyers.
Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.
D
1700
170
70
170
900
70
370
9000
170
5000
500
3000
430
D
1700
90
130
30
3000
170
900
90
20
90
70
2000
900
170
430
170
Round 1,724 to the nearest hundredD
Round 17 to the nearest tenP
Round 167 to the nearest tenE
Round 4,501 to the nearest thousandF
Round 530 to the nearest hundredO
Round 71 to the nearest tenT
Round 31 to the nearest tenL
Round 2,549 to the nearest thousandU
Round 88 to the nearest tenA
Round 2,112 to the nearest thousandS
Round 8,764 to the nearest thousandV
Round 430 to the nearest tenN
Round 131 to the nearest tenB
Round 891 to the nearest hundredC
Round 370 to the nearest tenI
0/15 letters found
Clue 5
Missing addends — the last clue
You calculate how many extra energy crystals are needed to fill the vessel.
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
23 + ___ = 33
39 + ___ = 42
6 + ___ = 11
35 + ___ = 37
2 + ___ = 3
38 + ___ = 45
18 + ___ = 22
17 + ___ = 25
9 + ___ = 15
37 + ___ = 49
38 + ___ = 49
Step 2 — cross out the sentence with each answer
1.The villain soared across the sky island, then slung a heavy map pouch.
2.The villain blasted off with jet boots, then pinned on a brass compass badge.
3.The villain swung from the tall watchtower, then peered through a brass spyglass.
4.The villain tossed a thick smoke bomb, then tucked away a bronze whistle.
5.The villain soared across the sky island, then peered through a brass spyglass.
6.The villain tossed a thick smoke bomb, then fired a bright signal flare.
7.The villain swung from the tall watchtower, then tucked away a bronze whistle.
8.The villain blew a sharp wind whistle, then tucked away a bronze whistle.
9.The villain tossed a thick smoke bomb, then pinned on a brass compass badge.
10.The villain blasted off with jet boots, then fired a bright signal flare.
11.The villain blasted off with jet boots, then tucked away a bronze whistle.
12.The villain swung from the tall watchtower, then fired a bright signal flare.
Solve it
Name the culprit
Choose the one suspect left standing.
Answer Key — The Mystery of Cloud Archipelago
Culprit: Lookout Maya (Smoke Bombs · Compass Badge · Right-handed · Blue Cap · Loud Whistles)
- Clue 1 (Multiplication facts (1-12)): "THE VILLAIN DOES NOT CARRY A MAP POUCH"12 × 10 = 120 (T) · 4 × 1 = 4 (C) · 5 × 5 = 25 (H) · 9 × 3 = 27 (U) · 7 × 5 = 35 (S) · 7 × 7 = 49 (O) · 9 × 2 = 18 (R) · 7 × 3 = 21 (I) · 10 × 11 = 110 (M) · 6 × 9 = 54 (E) · 2 × 8 = 16 (N) · 2 × 7 = 14 (V) · 5 × 9 = 45 (L) · 1 × 1 = 1 (Y) · 11 × 7 = 77 (D) · 12 × 2 = 24 (A) · 5 × 12 = 60 (P)
- Clue 2 (Addition): "WITNESS SAW RIGHT HANDED GRIP ON ROPE"3144 + 1908 = 5052 (W) · 3496 + 6240 = 9736 (P) · 2755 + 3918 = 6673 (I) · 1841 + 2548 = 4389 (E) · 3062 + 4719 = 7781 (O) · 4620 + 2315 = 6935 (A) · 6066 + 3585 = 9651 (S) · 3020 + 6233 = 9253 (T) · 1949 + 3022 = 4971 (N) · 4311 + 5023 = 9334 (G) · 2390 + 1726 = 4116 (R) · 1533 + 1181 = 2714 (D) · 2345 + 4622 = 6967 (H)
- Clue 3 (Skip counting): "THE VILLAIN RAN FROM LOUD WHISTLES"Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, ___, 42, 45 = 39 (T) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, ___, 24, 26 = 22 (A) · Skip-count by 2s. Fill the blank: 2, 4, 6, ___, 10, 12 = 8 (N) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, ___, 140, 150 = 130 (H) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, ___, 60, 65 = 55 (L) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, ___, 30, 33 = 27 (I) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, ___, 28, 30 = 26 (E) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, ___, 110, 120 = 100 (O) · Skip-count by 5s. Fill the blank: 5, 10, ___, 20, 25 = 15 (W) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, ___, 27, 30 = 24 (M) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, ___, 60, 70 = 50 (S) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, ___, 40, 45 = 35 (U) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, ___, 50, 55 = 45 (F) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, ___, 30, 32 = 28 (R) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, ___, 65, 70 = 60 (V) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, ___, 100, 110 = 90 (D)
- Clue 4 (Rounding): "DETECTIVE FOUND A BLUE CAP AT SCENE"Round 1,724 to the nearest hundred = 1700 (D) · Round 17 to the nearest ten = 20 (P) · Round 167 to the nearest ten = 170 (E) · Round 4,501 to the nearest thousand = 5000 (F) · Round 530 to the nearest hundred = 500 (O) · Round 71 to the nearest ten = 70 (T) · Round 31 to the nearest ten = 30 (L) · Round 2,549 to the nearest thousand = 3000 (U) · Round 88 to the nearest ten = 90 (A) · Round 2,112 to the nearest thousand = 2000 (S) · Round 8,764 to the nearest thousand = 9000 (V) · Round 430 to the nearest ten = 430 (N) · Round 131 to the nearest ten = 130 (B) · Round 891 to the nearest hundred = 900 (C) · Round 370 to the nearest ten = 370 (I)
- Clue 5 (Missing addends): surviving statement (box 9) → Lookout Maya23 + ___ = 33 = 10 · 39 + ___ = 42 = 3 · 6 + ___ = 11 = 5 · 35 + ___ = 37 = 2 · 2 + ___ = 3 = 1 · 38 + ___ = 45 = 7 · 18 + ___ = 22 = 4 · 17 + ___ = 25 = 8 · 9 + ___ = 15 = 6 · 37 + ___ = 49 = 12 · 38 + ___ = 49 = 11
About this mystery
- Grade level
- Grade 4 math
- Math topics
- Multiplication, Addition, Skip counting, Rounding, Missing addends
- Reading level
- grades 3-4
- Theme
- The Mystery of Cloud Archipelago — set in Nimba Cloud Archipelago
- Format
- Interactive online & printable worksheet with answer key
- Solution
- One unique, verified culprit among 21 suspects