Grade 4Reading: grades 3-4MultiplicationRoundingAdditionSubtractionDivision
The Mystery of Mapmaker Bay
The Golden Compass has vanished from the Treehouse Camp! The Chief Archivist needs your help to track down the sneaky explorer who took it before the island ferry departs.
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 Gear | Secondary Gear | Dominant Hand | Hair Style | Foil |
|---|---|---|---|---|---|
| Davy Crockett | Night Goggles | Mini Flashlight | Left Handed | Curly Red Hair | Loud Whistles |
| Sacagawea | Pocket Glider | Decoder Ring | Right Handed | Straight Blonde Hair | Loud Whistles |
| Mary Anning | Grappling Hook | Walkie Talkie | Left Handed | Straight Blonde Hair | Loud Whistles |
| Dian Fossey | Spy Drone | Smoke Bomb | Right Handed | Spiky Brown Hair | Sweet Treats |
| Amelia Earhart | Grappling Hook | Smoke Bomb | Left Handed | Curly Red Hair | Loud Whistles |
| Alexander Humboldt | Pocket Glider | Decoder Ring | Right Handed | Curly Red Hair | Sweet Treats |
| Jane Goodall | Grappling Hook | Decoder Ring | Right Handed | Straight Blonde Hair | Loud Whistles |
| Bessie Coleman | Laser Pointer | Smoke Bomb | Left Handed | Spiky Brown Hair | Loud Whistles |
| Daniel Boone | Night Goggles | Secret Ink | Right Handed | Straight Blonde Hair | Shiny Coins |
| Buzz Aldrin | Laser Pointer | Decoder Ring | Right Handed | Spiky Brown Hair | Loud Whistles |
| Nellie Bly | Grappling Hook | Decoder Ring | Right Handed | Spiky Brown Hair | Sweet Treats |
| Steve Irwin | Spy Drone | Walkie Talkie | Right Handed | Straight Blonde Hair | Loud Whistles |
| Matthew Henson | Laser Pointer | Smoke Bomb | Right Handed | Straight Blonde Hair | Loud Whistles |
| Laura Dekker | Spy Drone | Mini Flashlight | Left Handed | Straight Blonde Hair | Sweet Treats |
| Jeanne Baret | Spy Drone | Decoder Ring | Right Handed | Spiky Brown Hair | Sweet Treats |
| Sally Ride | Night Goggles | Smoke Bomb | Right Handed | Curly Red Hair | Loud Whistles |
| Roald Amundsen | Spy Drone | Walkie Talkie | Right Handed | Straight Blonde Hair | Shiny Coins |
| Mae Jemison | Grappling Hook | Mini Flashlight | Right Handed | Straight Blonde Hair | Loud Whistles |
| Ibn Battuta | Laser Pointer | Secret Ink | Left Handed | Spiky Brown Hair | Loud Whistles |
| Robert Peary | Laser Pointer | Decoder Ring | Left Handed | Straight Blonde Hair | Loud Whistles |
| Neil Armstrong | Spy Drone | Smoke Bomb | Right Handed | Straight Blonde Hair | Loud Whistles |
Clue 1
Multiplication facts (1-12)
We found the gear room in a mess. There were several rows of shelves, with climbing ropes on each shelf. If we multiply them together, we get a clue about the thief's 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
30
99
15
81
70
21
21
5
70
108
50
80
15
7
108
80
T
30
56
7
15
7
66
80
77
15
9
80
66
9
7
5 × 6 =T
9 × 11 =H
7 × 3 =L
5 × 3 =E
5 × 10 =D
1 × 9 =B
7 × 11 =K
9 × 9 =V
8 × 10 =O
9 × 12 =N
6 × 11 =M
7 × 10 =I
1 × 7 =S
1 × 5 =A
7 × 8 =U
0/15 letters found
Clue 2
Rounding
The ancient security screen is fuzzy. The dials only show numbers rounded to the nearest ten. Round the power level to unlock the clue on the screen.
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
370
2300
700
7000
1100
700
430
70
3700
170
230
7000
230
T
370
50
1300
5000
430
7000
1300
230
290
2300
T
370
2300
430
1100
500
700
500
Round 370 to the nearest tenT
Round 2,324 to the nearest hundredH
Round 288 to the nearest tenG
Round 507 to the nearest hundredD
Round 168 to the nearest tenV
Round 69 to the nearest tenK
Round 3,704 to the nearest hundredY
Round 49 to the nearest tenO
Round 7,321 to the nearest thousandS
Round 1,346 to the nearest hundredR
Round 431 to the nearest tenA
Round 674 to the nearest hundredE
Round 4,871 to the nearest thousandW
Round 227 to the nearest tenI
Round 1,118 to the nearest hundredN
0/15 letters found
Clue 3
Addition
We need to combine the weight of the gold coins and the silver keys we found. Add the two piles together to find the secret safe combination!
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
6085
2279
4068
8708
7893
4068
7507
3285
9469
6983
7893
8708
7507
6111
7507
5044
5163
9469
5054
4766
6627
5054
6983
6530
6111
2279
7398
8708
T
6085
6627
4068
8708
4048 + 2037 =T
3562 + 5146 =S
3665 + 2446 =W
3337 + 1707 =Y
1337 + 1948 =K
5031 + 2862 =N
2999 + 3984 =U
2994 + 4404 =I
1961 + 4569 =D
3536 + 1627 =F
1741 + 3313 =O
3335 + 3292 =L
5605 + 3864 =R
4183 + 3324 =A
1222 + 1057 =H
1642 + 2426 =E
3325 + 1441 =M
0/17 letters found
Clue 4
Subtraction
The thief drained the energy pack of our flashlight. Subtract the remaining power from the total to see how long they were in the secret room.
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
5963
6979
1484
2068
6010
6344
7307
1422
8202
7323
8055
3850
2811
7852
8202
3962
6782
2068
6344
7307
6979
7852
8055
3850
7323
2068
6344
8202
7852
6979
2550
8055
1332
6302 - 339 =W
11667 - 3815 =H
11531 - 3329 =T
1837 - 505 =P
7463 - 156 =D
9683 - 2704 =E
4302 - 340 =B
6547 - 2697 =I
11409 - 4627 =L
5103 - 2553 =M
10545 - 4201 =N
4207 - 1396 =G
10314 - 4304 =U
10041 - 1986 =A
8128 - 805 =R
3110 - 1688 =S
4297 - 2229 =O
6213 - 4729 =F
0/18 letters found
Clue 5
Division facts (1-12) — the last clue
We found a pile of ancient map pieces. If we divide them evenly among our team members, the leftover pieces will reveal the final clue.
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
54 ÷ 6 = ?
10 ÷ 10 = ?
6 ÷ 2 = ?
121 ÷ 11 = ?
4 ÷ 1 = ?
18 ÷ 3 = ?
21 ÷ 3 = ?
40 ÷ 5 = ?
55 ÷ 11 = ?
24 ÷ 2 = ?
12 ÷ 6 = ?
Step 2 — cross out the sentence with each answer
1.The villain swings across the river with a grappling hook, then examines the dusty lock with a mini flashlight.
2.The villain scouts the area with a spy drone, then writes a hidden clue using secret ink.
3.The villain scouts the area with a spy drone, then whispers to an accomplice over a walkie talkie.
4.The villain searches in the dark with night goggles, then cracks the ancient code with a decoder ring.
5.The villain searches in the dark with night goggles, then vanishes into the shadows with a smoke bomb.
6.The villain points out the path with a laser pointer, then whispers to an accomplice over a walkie talkie.
7.The villain points out the path with a laser pointer, then writes a hidden clue using secret ink.
8.The villain swings across the river with a grappling hook, then writes a hidden clue using secret ink.
9.The villain sails over the trees with a pocket glider, then cracks the ancient code with a decoder ring.
10.The villain swings across the river with a grappling hook, then cracks the ancient code with a decoder ring.
11.The villain points out the path with a laser pointer, then cracks the ancient code with a decoder ring.
12.The villain sails over the trees with a pocket glider, then writes a hidden clue using secret ink.
Solve it
Name the culprit
Choose the one suspect left standing.
Answer Key — The Mystery of Mapmaker Bay
Culprit: Jane Goodall (Grappling Hook · Decoder Ring · Right Handed · Straight Blonde Hair · Loud Whistles)
- Clue 1 (Multiplication facts (1-12)): "THE VILLAIN DOES NOT USE SMOKE BOMBS"5 × 6 = 30 (T) · 9 × 11 = 99 (H) · 7 × 3 = 21 (L) · 5 × 3 = 15 (E) · 5 × 10 = 50 (D) · 1 × 9 = 9 (B) · 7 × 11 = 77 (K) · 9 × 9 = 81 (V) · 8 × 10 = 80 (O) · 9 × 12 = 108 (N) · 6 × 11 = 66 (M) · 7 × 10 = 70 (I) · 1 × 7 = 7 (S) · 1 × 5 = 5 (A) · 7 × 8 = 56 (U)
- Clue 2 (Rounding): "THE SNEAKY VISITOR WAS RIGHT HANDED"Round 370 to the nearest ten = 370 (T) · Round 2,324 to the nearest hundred = 2300 (H) · Round 288 to the nearest ten = 290 (G) · Round 507 to the nearest hundred = 500 (D) · Round 168 to the nearest ten = 170 (V) · Round 69 to the nearest ten = 70 (K) · Round 3,704 to the nearest hundred = 3700 (Y) · Round 49 to the nearest ten = 50 (O) · Round 7,321 to the nearest thousand = 7000 (S) · Round 1,346 to the nearest hundred = 1300 (R) · Round 431 to the nearest ten = 430 (A) · Round 674 to the nearest hundred = 700 (E) · Round 4,871 to the nearest thousand = 5000 (W) · Round 227 to the nearest ten = 230 (I) · Round 1,118 to the nearest hundred = 1100 (N)
- Clue 3 (Addition): "THE SNEAK RUNS AWAY FROM LOUD WHISTLES"4048 + 2037 = 6085 (T) · 3562 + 5146 = 8708 (S) · 3665 + 2446 = 6111 (W) · 3337 + 1707 = 5044 (Y) · 1337 + 1948 = 3285 (K) · 5031 + 2862 = 7893 (N) · 2999 + 3984 = 6983 (U) · 2994 + 4404 = 7398 (I) · 1961 + 4569 = 6530 (D) · 3536 + 1627 = 5163 (F) · 1741 + 3313 = 5054 (O) · 3335 + 3292 = 6627 (L) · 5605 + 3864 = 9469 (R) · 4183 + 3324 = 7507 (A) · 1222 + 1057 = 2279 (H) · 1642 + 2426 = 4068 (E) · 3325 + 1441 = 4766 (M)
- Clue 4 (Subtraction): "WE FOUND STRAIGHT BLONDE HAIR ON THE MAP"6302 - 339 = 5963 (W) · 11667 - 3815 = 7852 (H) · 11531 - 3329 = 8202 (T) · 1837 - 505 = 1332 (P) · 7463 - 156 = 7307 (D) · 9683 - 2704 = 6979 (E) · 4302 - 340 = 3962 (B) · 6547 - 2697 = 3850 (I) · 11409 - 4627 = 6782 (L) · 5103 - 2553 = 2550 (M) · 10545 - 4201 = 6344 (N) · 4207 - 1396 = 2811 (G) · 10314 - 4304 = 6010 (U) · 10041 - 1986 = 8055 (A) · 8128 - 805 = 7323 (R) · 3110 - 1688 = 1422 (S) · 4297 - 2229 = 2068 (O) · 6213 - 4729 = 1484 (F)
- Clue 5 (Division facts (1-12)): surviving statement (box 10) → Jane Goodall54 ÷ 6 = 9 · 10 ÷ 10 = 1 · 6 ÷ 2 = 3 · 121 ÷ 11 = 11 · 4 ÷ 1 = 4 · 18 ÷ 3 = 6 · 21 ÷ 3 = 7 · 40 ÷ 5 = 8 · 55 ÷ 11 = 5 · 24 ÷ 2 = 12 · 12 ÷ 6 = 2
About this mystery
- Grade level
- Grade 4 math
- Math topics
- Multiplication, Rounding, Addition, Subtraction, Division
- Reading level
- grades 3-4
- Theme
- The Mystery of Mapmaker Bay — set in A sun-drenched island filled with hidden treehouses, rope bridges, and forgotten ruins.
- Format
- Interactive online & printable worksheet with answer key
- Solution
- One unique, verified culprit among 21 suspects