Grade 5Reading: grades 5-6Place valueAdditionSubtractionMultiplicationDivision
The Mystery of Whispering Island
The Golden Compass of Whispering Island has vanished from the Grand Treehouse! A rogue explorer snatched it right before our big expedition. We must track them down before they find the Lost Temple first.
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 | Signature Tool | Survival Badge | Navigation Tool | Explorer Hat | Fear |
|---|---|---|---|---|---|
| Jessie Flint | spyglass | knot tying | uses a map | pith helmet | scared of spiders |
| Chris Pine | spyglass | knot tying | uses a map | safari cap | dislikes mud |
| Sam Oakley | compact shovel | trail blazing | uses a map | safari cap | afraid of heights |
| Sandy Banks | compact shovel | weather tracking | uses a compass | bandana | dislikes mud |
| Terry Moss | climbing pick | trail blazing | uses a compass | pith helmet | afraid of heights |
| Morgan Finch | compact shovel | knot tying | uses a map | safari cap | scared of spiders |
| Ren Hunter | laser flashlight | fire making | uses a compass | safari cap | dislikes mud |
| Jordan Wells | grappling hook | weather tracking | uses a map | safari cap | dislikes mud |
| Kelly Ridge | grappling hook | first aid | uses a compass | safari cap | dislikes mud |
| Val Valley | climbing pick | fire making | uses a compass | safari cap | dislikes mud |
| Taylor Brooks | climbing pick | fire making | uses a compass | bandana | dislikes mud |
| Pat Riley | spyglass | weather tracking | uses a compass | safari cap | dislikes mud |
| Ranger Evans | spyglass | fire making | uses a compass | bandana | scared of spiders |
| Casey Vance | grappling hook | first aid | uses a map | safari cap | dislikes mud |
| Camper Cody | compact shovel | first aid | uses a compass | safari cap | scared of spiders |
| Kit Carver | climbing pick | trail blazing | uses a compass | safari cap | dislikes mud |
| Alex Rivera | spyglass | knot tying | uses a compass | safari cap | afraid of heights |
| Tracker Thompson | spyglass | trail blazing | uses a map | safari cap | dislikes mud |
| Jamie Wilder | compact shovel | knot tying | uses a map | safari cap | afraid of heights |
| Skyler Cruz | compact shovel | first aid | uses a compass | safari cap | dislikes mud |
| Dana Stone | spyglass | trail blazing | uses a map | bandana | dislikes mud |
Clue 1
Place value
We found a locked GPS device dropped near the treehouse ladder. To unlock the screen and reveal the first clue, we need to find the digit in the thousands place of the altitude reading.
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
6000
8000
70
300
100
1000
800
70
70
700
7000
2000
100
300
70
300
5000
100
70
400
80
100
T
6000
8000
60
9000
70
600
3000
300
400
T
6000
60
3000
5000
What is the value of the 6 in 26,799?T
What is the value of the 7 in 935,274?E
What is the value of the 7 in 987,862?P
What is the value of the 4 in 897,420?S
What is the value of the 3 in 863,215?I
What is the value of the 9 in 69,208?V
What is the value of the 8 in 498,562?H
What is the value of the 8 in 553,866?U
What is the value of the 6 in 19,631?F
What is the value of the 2 in 32,074?L
What is the value of the 3 in 94,321?R
What is the value of the 1 in 708,173?O
What is the value of the 5 in 905,939?D
What is the value of the 7 in 212,741?X
What is the value of the 1 in 521,583?G
What is the value of the 6 in 518,067?A
What is the value of the 8 in 400,484?N
0/17 letters found
Clue 2
Addition
A crumpled packing list lies on the trail. We must add up the weights of the canteen, the sleeping bag, and the portable radio to see how much gear the runaway carried.
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
6654
2465
2184
3385
7649
9641
9641
2703
7649
8327
8327
2703
3385
7649
5466
2703
T
6654
2184
5917
2494
7649
T
6654
2465
2703
8177
7911
2885
5880
2703
5917
5917
3670 + 2984 =T
1938 + 3528 =G
2315 + 3602 =S
1096 + 1369 =H
4030 + 4297 =N
1042 + 1661 =A
1701 + 1184 =M
938 + 1556 =W
4230 + 3681 =O
3058 + 4591 =I
666 + 1518 =E
3234 + 4943 =C
4818 + 4823 =L
3391 + 2489 =P
2114 + 1271 =V
0/15 letters found
Clue 3
Subtraction
Our team checked the river depth gauge near the rope bridge. By subtracting yesterday's low-water level from today's high-water mark, we can calculate how deep the crossing was.
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
7805
8808
2768
8213
1255
7925
8427
6662
3382
T
7805
1248
8692
5281
3382
2110
2768
2110
T
7805
8808
2768
7115
1255
2110
2110
1406
8427
1248
T
7805
8808
10638 - 2833 =T
5599 - 318 =O
2927 - 1672 =U
12412 - 3985 =P
4137 - 2731 =Y
11706 - 3014 =V
11464 - 3539 =L
6743 - 4633 =D
9097 - 2435 =R
4063 - 681 =I
12370 - 4157 =C
2580 - 1332 =A
10729 - 1921 =H
5094 - 2326 =E
7707 - 592 =M
0/15 letters found
Clue 4
Multiplication facts (1-12)
Ancient stone stairs lead up the misty ridge in equal rows. If there are several steps in each row, multiplying them will reveal the total steps the suspect climbed to escape.
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
45
56
80
120
33
120
48
80
72
T
45
20
1
64
80
81
44
64
80
80
32
120
81
90
81
64
54
72
81
48
9 × 5 =T
12 × 10 =S
7 × 8 =H
10 × 8 =E
5 × 4 =W
8 × 8 =R
9 × 9 =A
10 × 9 =F
8 × 4 =N
11 × 4 =G
9 × 6 =I
1 × 1 =O
12 × 6 =C
8 × 6 =P
3 × 11 =U
0/15 letters found
Clue 5
Division facts (1-12) — the last clue
We recovered a bundle of climbing ropes left at the gorge. If we divide the total length of the rope evenly among the search team members, we will find how many meters each scout gets.
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
9 ÷ 3 = ?
63 ÷ 9 = ?
84 ÷ 7 = ?
36 ÷ 9 = ?
25 ÷ 5 = ?
10 ÷ 1 = ?
12 ÷ 2 = ?
22 ÷ 11 = ?
96 ÷ 12 = ?
99 ÷ 11 = ?
9 ÷ 9 = ?
Step 2 — cross out the sentence with each answer
1.The villain scouted the path ahead with a spyglass, then secured the escape rope with expert knot tying.
2.The villain scaled the muddy cliff using a climbing pick, then timed the quick getaway using weather tracking.
3.The villain scaled the muddy cliff using a climbing pick, then marked the getaway route by trail blazing.
4.The villain cleared the dark cave with a laser flashlight, then timed the quick getaway using weather tracking.
5.The villain scaled the muddy cliff using a climbing pick, then patched up a scraped knee with first aid.
6.The villain swung across the gorge using a grappling hook, then patched up a scraped knee with first aid.
7.The villain scaled the muddy cliff using a climbing pick, then warmed up the camp by fire making.
8.The villain cleared the dark cave with a laser flashlight, then secured the escape rope with expert knot tying.
9.The villain cleared the dark cave with a laser flashlight, then marked the getaway route by trail blazing.
10.The villain dug up the hidden trail marker with a compact shovel, then secured the escape rope with expert knot tying.
11.The villain scouted the path ahead with a spyglass, then timed the quick getaway using weather tracking.
12.The villain cleared the dark cave with a laser flashlight, then warmed up the camp by fire making.
Solve it
Name the culprit
Choose the one suspect left standing.
Answer Key — The Mystery of Whispering Island
Culprit: Pat Riley (spyglass · weather tracking · uses a compass · safari cap · dislikes mud)
- Clue 1 (Place value): "THE ROGUE EXPLORER DOES NOT HAVE FIRST AID"What is the value of the 6 in 26,799? = 6000 (T) · What is the value of the 7 in 935,274? = 70 (E) · What is the value of the 7 in 987,862? = 7000 (P) · What is the value of the 4 in 897,420? = 400 (S) · What is the value of the 3 in 863,215? = 3000 (I) · What is the value of the 9 in 69,208? = 9000 (V) · What is the value of the 8 in 498,562? = 8000 (H) · What is the value of the 8 in 553,866? = 800 (U) · What is the value of the 6 in 19,631? = 600 (F) · What is the value of the 2 in 32,074? = 2000 (L) · What is the value of the 3 in 94,321? = 300 (R) · What is the value of the 1 in 708,173? = 100 (O) · What is the value of the 5 in 905,939? = 5000 (D) · What is the value of the 7 in 212,741? = 700 (X) · What is the value of the 1 in 521,583? = 1000 (G) · What is the value of the 6 in 518,067? = 60 (A) · What is the value of the 8 in 400,484? = 80 (N)
- Clue 2 (Addition): "THE VILLAIN NAVIGATES WITH A COMPASS"3670 + 2984 = 6654 (T) · 1938 + 3528 = 5466 (G) · 2315 + 3602 = 5917 (S) · 1096 + 1369 = 2465 (H) · 4030 + 4297 = 8327 (N) · 1042 + 1661 = 2703 (A) · 1701 + 1184 = 2885 (M) · 938 + 1556 = 2494 (W) · 4230 + 3681 = 7911 (O) · 3058 + 4591 = 7649 (I) · 666 + 1518 = 2184 (E) · 3234 + 4943 = 8177 (C) · 4818 + 4823 = 9641 (L) · 3391 + 2489 = 5880 (P) · 2114 + 1271 = 3385 (V)
- Clue 3 (Subtraction): "THE CULPRIT AVOIDED THE MUDDY PATH"10638 - 2833 = 7805 (T) · 5599 - 318 = 5281 (O) · 2927 - 1672 = 1255 (U) · 12412 - 3985 = 8427 (P) · 4137 - 2731 = 1406 (Y) · 11706 - 3014 = 8692 (V) · 11464 - 3539 = 7925 (L) · 6743 - 4633 = 2110 (D) · 9097 - 2435 = 6662 (R) · 4063 - 681 = 3382 (I) · 12370 - 4157 = 8213 (C) · 2580 - 1332 = 1248 (A) · 10729 - 1921 = 8808 (H) · 5094 - 2326 = 2768 (E) · 7707 - 592 = 7115 (M)
- Clue 4 (Multiplication facts (1-12)): "THE SUSPECT WORE A GREEN SAFARI CAP"9 × 5 = 45 (T) · 12 × 10 = 120 (S) · 7 × 8 = 56 (H) · 10 × 8 = 80 (E) · 5 × 4 = 20 (W) · 8 × 8 = 64 (R) · 9 × 9 = 81 (A) · 10 × 9 = 90 (F) · 8 × 4 = 32 (N) · 11 × 4 = 44 (G) · 9 × 6 = 54 (I) · 1 × 1 = 1 (O) · 12 × 6 = 72 (C) · 8 × 6 = 48 (P) · 3 × 11 = 33 (U)
- Clue 5 (Division facts (1-12)): surviving statement (box 11) → Pat Riley9 ÷ 3 = 3 · 63 ÷ 9 = 7 · 84 ÷ 7 = 12 · 36 ÷ 9 = 4 · 25 ÷ 5 = 5 · 10 ÷ 1 = 10 · 12 ÷ 2 = 6 · 22 ÷ 11 = 2 · 96 ÷ 12 = 8 · 99 ÷ 11 = 9 · 9 ÷ 9 = 1
About this mystery
- Grade level
- Grade 5 math
- Math topics
- Place value, Addition, Subtraction, Multiplication, Division
- Reading level
- grades 5-6
- Theme
- The Mystery of Whispering Island — set in the misty canopy of Whispering Island
- Format
- Interactive online & printable worksheet with answer key
- Solution
- One unique, verified culprit among 21 suspects