🌊 MermaidsGrade 6Reading: grades 5-6PercentagesExponentsOrder of operationsMultiplicationDivision

The Mystery of the Stolen Star-Pearl

When the glowing Star-Pearl vanished from the central vault of Coral Ridge Lagoon, the underwater council called in their top detective squad. Footprints in the sea sand and mysterious power surges left clues across the reef.

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	Ocean Power	Equipment	Dominant Fin	Hair Color	Weakness
Nautilus	water shield	glow lantern	RIGHT HANDED	DEEP BLUE HAIR	LOUD SOUNDS
Cora	sonic wave	shell whistle	RIGHT HANDED	CORAL RED HAIR	LOUD SOUNDS
Muriel	sonic wave	glow lantern	RIGHT HANDED	SEA GREEN HAIR	LOUD SOUNDS
Marina	current control	pearl compass	LEFT HANDED	DEEP BLUE HAIR	BRIGHT LIGHT
Glaucus	sonic wave	glow lantern	LEFT HANDED	DEEP BLUE HAIR	STRONG CURRENTS
Pearl	tidal blast	glow lantern	LEFT HANDED	CORAL RED HAIR	BRIGHT LIGHT
Coralia	water shield	kelp net	LEFT HANDED	CORAL RED HAIR	BRIGHT LIGHT
Nerida	coral shaping	shell whistle	LEFT HANDED	DEEP BLUE HAIR	BRIGHT LIGHT
Kailani	tidal blast	kelp net	RIGHT HANDED	CORAL RED HAIR	STRONG CURRENTS
Ray	current control	pearl compass	LEFT HANDED	DEEP BLUE HAIR	STRONG CURRENTS
Caspian	sonic wave	pearl compass	LEFT HANDED	DEEP BLUE HAIR	BRIGHT LIGHT
Ariel	tidal blast	kelp net	RIGHT HANDED	DEEP BLUE HAIR	BRIGHT LIGHT
Urchin	tidal blast	silver trident	LEFT HANDED	DEEP BLUE HAIR	STRONG CURRENTS
Kai	water shield	silver trident	LEFT HANDED	DEEP BLUE HAIR	BRIGHT LIGHT
Finnigan	tidal blast	shell whistle	RIGHT HANDED	DEEP BLUE HAIR	LOUD SOUNDS
Sirenna	tidal blast	shell whistle	LEFT HANDED	DEEP BLUE HAIR	LOUD SOUNDS
Callum	current control	glow lantern	LEFT HANDED	DEEP BLUE HAIR	BRIGHT LIGHT
Dylan	coral shaping	glow lantern	RIGHT HANDED	DEEP BLUE HAIR	LOUD SOUNDS
Oceanus	sonic wave	silver trident	LEFT HANDED	DEEP BLUE HAIR	STRONG CURRENTS
Triton	tidal blast	silver trident	LEFT HANDED	CORAL RED HAIR	STRONG CURRENTS
Maris	water shield	shell whistle	RIGHT HANDED	DEEP BLUE HAIR	LOUD SOUNDS

Clue 1

Percentages

The Lagoon Patrol calculated what percentage of the vault locks were tampered with to reveal the first 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.

20% of 135 =T

25% of 112 =W

60% of 65 =H

10% of 380 =I

60% of 50 =R

5% of 40 =S

20% of 145 =E

20% of 55 =U

5% of 720 =P

40% of 60 =N

10% of 230 =L

25% of 20 =C

10% of 350 =Y

25% of 104 =D

25% of 4 =O

10% of 340 =A

0/16 letters found

Clue 2

Exponents

To decipher an encrypted sonar signal, Guard Marina calculated exponential power increases from the hydro-beacons.

Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.

324

343

289

100

256

128

196

400

289

256

216

121

324

128

196

400

3^4 =T

2^3 =S

3^3 =P

2^7 =A

16^2 =I

11^2 =L

20^2 =D

14^2 =N

7^3 =C

6^3 =M

4^2 =E

10^2 =R

3^2 =F

4^3 =U

17^2 =W

18^2 =H

0/16 letters found

Clue 3

Order of operations

Analyzing the multi-step security cipher required evaluating mathematical expressions using the proper order of operations.

Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.

11 × 3 - 2 =T

43 + 3 × 9 =H

22 + 5 × 6 =L

59 + 7 × 3 =I

8 × 6 - 20 =G

9 × 3 - 21 =R

8 + 8 × 2 =S

5 × 11 - 15 =E

9 + 3 × 4 =A

1 + 5 × 2 =D

10 × 7 - 5 =W

9 × 3 - 5 =Y

8 + 2 × 6 =B

1 + 2 × 4 =V

4 × 10 - 23 =N

0/15 letters found

Clue 4

Multiplication facts (1-12)

By counting equal rows of giant clams in the storage beds, the team multiplied to find the exact inventory.

Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.

110

7 × 12 =F

3 × 9 =P

11 × 2 =T

10 × 7 =N

3 × 6 =I

3 × 1 =O

12 × 6 =C

7 × 7 =B

10 × 4 =E

5 × 3 =A

1 × 9 =K

1 × 6 =R

2 × 5 =U

8 × 12 =D

4 × 6 =L

9 × 10 =H

11 × 10 =S

0/17 letters found

Clue 5

Division facts (1-12) — the last clue

Dividing the recovery zone into equal search grids for each swimmer narrowed down where the suspect hid.

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

63 ÷ 9 = ?

35 ÷ 7 = ?

6 ÷ 1 = ?

16 ÷ 4 = ?

11 ÷ 11 = ?

99 ÷ 9 = ?

8 ÷ 1 = ?

8 ÷ 4 = ?

9 ÷ 3 = ?

63 ÷ 7 = ?

12 ÷ 1 = ?

Step 2 — cross out the sentence with each answer

1.The villain raised a water shield, then checked directions on a pearl compass.

2.The villain unleashed a tidal blast, then swam away with a silver trident.

3.The villain used coral shaping magic, then lit the path with a glow lantern.

4.The villain used coral shaping magic, then signaled with a shell whistle.

5.The villain manipulated the current control, then checked directions on a pearl compass.

6.The villain raised a water shield, then swam away with a silver trident.

7.The villain sent out a sonic wave, then checked directions on a pearl compass.

8.The villain unleashed a tidal blast, then lit the path with a glow lantern.

9.The villain unleashed a tidal blast, then secured the stash in a kelp net.

10.The villain manipulated the current control, then lit the path with a glow lantern.

11.The villain raised a water shield, then lit the path with a glow lantern.

12.The villain raised a water shield, then signaled with a shell whistle.

Solve it

Name the culprit

Choose the one suspect left standing.

Answer Key — The Mystery of the Stolen Star-Pearl

Culprit: Callum (current control · glow lantern · LEFT HANDED · DEEP BLUE HAIR · BRIGHT LIGHT)

Clue 1 (Percentages): "THE SUSPECT DOES NOT CARRY A SHELL WHISTLE"
20% of 135 = 27 (T) · 25% of 112 = 28 (W) · 60% of 65 = 39 (H) · 10% of 380 = 38 (I) · 60% of 50 = 30 (R) · 5% of 40 = 2 (S) · 20% of 145 = 29 (E) · 20% of 55 = 11 (U) · 5% of 720 = 36 (P) · 40% of 60 = 24 (N) · 10% of 230 = 23 (L) · 25% of 20 = 5 (C) · 10% of 350 = 35 (Y) · 25% of 104 = 26 (D) · 25% of 4 = 1 (O) · 10% of 340 = 34 (A)
Clue 2 (Exponents): "THE SUSPECT WRITES AND SWIMS LEFT HANDED"
3^4 = 81 (T) · 2^3 = 8 (S) · 3^3 = 27 (P) · 2^7 = 128 (A) · 16^2 = 256 (I) · 11^2 = 121 (L) · 20^2 = 400 (D) · 14^2 = 196 (N) · 7^3 = 343 (C) · 6^3 = 216 (M) · 4^2 = 16 (E) · 10^2 = 100 (R) · 3^2 = 9 (F) · 4^3 = 64 (U) · 17^2 = 289 (W) · 18^2 = 324 (H)
Clue 3 (Order of operations): "THE VILLAIN WAS BLINDED BY BRIGHT LIGHT"
11 × 3 - 2 = 31 (T) · 43 + 3 × 9 = 70 (H) · 22 + 5 × 6 = 52 (L) · 59 + 7 × 3 = 80 (I) · 8 × 6 - 20 = 28 (G) · 9 × 3 - 21 = 6 (R) · 8 + 8 × 2 = 24 (S) · 5 × 11 - 15 = 40 (E) · 9 + 3 × 4 = 21 (A) · 1 + 5 × 2 = 11 (D) · 10 × 7 - 5 = 65 (W) · 9 × 3 - 5 = 22 (Y) · 8 + 2 × 6 = 20 (B) · 1 + 2 × 4 = 9 (V) · 4 × 10 - 23 = 17 (N)
Clue 4 (Multiplication facts (1-12)): "FOUND DEEP BLUE HAIR STRAND ON THE LOCK"
7 × 12 = 84 (F) · 3 × 9 = 27 (P) · 11 × 2 = 22 (T) · 10 × 7 = 70 (N) · 3 × 6 = 18 (I) · 3 × 1 = 3 (O) · 12 × 6 = 72 (C) · 7 × 7 = 49 (B) · 10 × 4 = 40 (E) · 5 × 3 = 15 (A) · 1 × 9 = 9 (K) · 1 × 6 = 6 (R) · 2 × 5 = 10 (U) · 8 × 12 = 96 (D) · 4 × 6 = 24 (L) · 9 × 10 = 90 (H) · 11 × 10 = 110 (S)
Clue 5 (Division facts (1-12)): surviving statement (box 10) → Callum
63 ÷ 9 = 7 · 35 ÷ 7 = 5 · 6 ÷ 1 = 6 · 16 ÷ 4 = 4 · 11 ÷ 11 = 1 · 99 ÷ 9 = 11 · 8 ÷ 1 = 8 · 8 ÷ 4 = 2 · 9 ÷ 3 = 3 · 63 ÷ 7 = 9 · 12 ÷ 1 = 12

About this mystery

Grade level: Grade 6 math
Math topics: Percentages, Exponents, Order of operations, Multiplication, Division
Reading level: grades 5-6
Theme: The Mystery of the Stolen Star-Pearl — set in Coral Ridge Lagoon
Format: Interactive online & printable worksheet with answer key
Solution: One unique, verified culprit among 21 suspects

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