🌊 MermaidsGrade 2Reading: grades 1-2AdditionSubtractionSkip countingPlace valueMissing addends
The Magic Pearl Mystery
Someone took the Magic Pearl from the Royal Reef Castle! The Royal Reef Keeper needs your help to find the sea thief.
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 | Swim Power | Magic Toy | Goggle Style | Tail Color | Fear |
|---|---|---|---|---|---|
| Marina | whirlpool spin | pearl ring | seaweed goggles | blue tail | loud sounds |
| Coral | dolphin dash | bubble wand | shell goggles | blue tail | loud sounds |
| Sirena | tidal wave | bubble wand | seaweed goggles | green tail | bright light |
| Melody | coral jump | clam drum | seaweed goggles | blue tail | tickles |
| Pearl | whirlpool spin | clam drum | shell goggles | blue tail | loud sounds |
| Sandy | dolphin dash | pearl ring | seaweed goggles | blue tail | tickles |
| Adella | tidal wave | pearl ring | shell goggles | pink tail | bright light |
| Cleo | whirlpool spin | shell flute | seaweed goggles | blue tail | tickles |
| Alana | whirlpool spin | star wand | seaweed goggles | green tail | tickles |
| Arista | kelp swing | clam drum | shell goggles | green tail | bright light |
| Shelly | dolphin dash | bubble wand | seaweed goggles | green tail | tickles |
| Andrina | whirlpool spin | clam drum | seaweed goggles | blue tail | tickles |
| Ocean | whirlpool spin | bubble wand | seaweed goggles | blue tail | tickles |
| Talia | whirlpool spin | pearl ring | shell goggles | pink tail | tickles |
| Attina | tidal wave | clam drum | shell goggles | blue tail | tickles |
| Chelsea | whirlpool spin | star wand | seaweed goggles | green tail | loud sounds |
| Madison | coral jump | star wand | shell goggles | green tail | bright light |
| Nixie | coral jump | pearl ring | seaweed goggles | blue tail | tickles |
| Delphine | whirlpool spin | shell flute | seaweed goggles | blue tail | loud sounds |
| Ariel | dolphin dash | pearl ring | shell goggles | blue tail | tickles |
| Nerida | dolphin dash | shell flute | seaweed goggles | pink tail | bright light |
Clue 1
Addition
A friendly sea turtle counts the shiny sea-glass pieces. He adds the green ones and the blue ones to find the total.
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
79
46
69
T
79
46
68
69
31
51
78
69
98
32
78
T
79
60
34
47
57
T
79
46
69
29
34
47
87
51
22
54
87
29 + 50 =T
18 + 16 =L
17 + 40 =Y
38 + 30 =I
37 + 23 =P
10 + 19 =C
15 + 36 =D
16 + 16 =N
50 + 37 =M
14 + 17 =F
45 + 33 =O
49 + 20 =E
12 + 10 =R
22 + 24 =H
18 + 36 =U
29 + 69 =S
16 + 31 =A
0/17 letters found
Clue 2
Subtraction
A school of tiny fish swims away from a hungry crab. We subtract the fish that left to see how many are still safe.
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
59
79
75
T
59
79
50
75
14
34
75
32
80
47
47
75
32
34
75
75
44
73
61
73
73
78
75
47
68 - 9 =T
107 - 32 =E
67 - 23 =D
75 - 2 =G
68 - 34 =W
48 - 16 =A
61 - 11 =I
89 - 28 =O
35 - 21 =F
92 - 13 =H
84 - 6 =L
114 - 34 =R
75 - 28 =S
0/13 letters found
Clue 3
Skip counting
Two baby dolphins swim in pairs. We count them by twos as they jump over the reef.
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
55
36
65
T
55
36
30
65
16
9
65
40
40
21
30
16
9
14
120
T
55
30
20
27
40
65
T
55
36
65
6
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, ___, 60, 65T
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, ___, 30, 33K
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, ___, 16, 18O
Skip-count by 3s. Fill the blank: 3, 6, ___, 12, 15Y
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, ___, 45, 50L
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, ___, 39, 42H
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, ___, 24, 27S
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, ___, 35, 40I
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, ___, 130, 140U
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, ___, 22, 24C
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, ___, 70, 75E
Skip-count by 2s. Fill the blank: 2, 4, ___, 8, 10M
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, ___, 18, 20F
0/13 letters found
Clue 4
Place value
A crab packs ocean pearls into boxes of ten. We count the boxes and the leftover single pearls.
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
37
87
43
84
63
55
62
88
89
66
18
55
11
97
56
63
87
89
36
88
56
87
What number has 3 tens and 7 ones?W
What number has 5 tens and 6 ones?L
What number has 3 tens and 6 ones?C
What number has 5 tens and 5 ones?N
What number has 6 tens and 6 ones?H
What number has 6 tens and 2 ones?D
What number has 6 tens and 3 ones?U
What number has 8 tens and 4 ones?O
What number has 8 tens and 8 ones?A
What number has 1 ten and 8 ones?I
What number has 1 ten and 1 one?Y
What number has 4 tens and 3 ones?F
What number has 9 tens and 7 ones?B
What number has 8 tens and 9 ones?S
What number has 8 tens and 7 ones?E
0/15 letters found
Clue 5
Missing addends — the last clue
We need ten pink shells to open the big stone gate. We have six shells and must find how many more we need.
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
4 + ___ = 13
8 + ___ = 18
9 + ___ = 13
1 + ___ = 4
5 + ___ = 13
8 + ___ = 13
7 + ___ = 18
8 + ___ = 14
3 + ___ = 10
3 + ___ = 4
9 + ___ = 21
Step 2 — cross out the sentence with each answer
1.The villain spun in a whirlpool spin, then tapped on a loud clam drum.
2.The villain spun in a whirlpool spin, then waved a magic bubble wand.
3.The villain leaped over a coral jump, then waved a magic bubble wand.
4.The villain spun in a whirlpool spin, then played a tune on a shell flute.
5.The villain did a fast dolphin dash, then tapped on a loud clam drum.
6.The villain swung on a long kelp swing, then played a tune on a shell flute.
7.The villain swung on a long kelp swing, then tapped on a loud clam drum.
8.The villain did a fast dolphin dash, then waved a magic bubble wand.
9.The villain leaped over a coral jump, then polished a shiny pearl ring.
10.The villain did a fast dolphin dash, then polished a shiny pearl ring.
11.The villain leaped over a coral jump, then played a tune on a shell flute.
12.The villain did a fast dolphin dash, then shined a bright star wand.
Solve it
Name the culprit
Choose the one suspect left standing.
Answer Key — The Magic Pearl Mystery
Culprit: Ocean (whirlpool spin · bubble wand · seaweed goggles · blue tail · tickles)
- Clue 1 (Addition): "THE THIEF DOES NOT PLAY THE CLAM DRUM"29 + 50 = 79 (T) · 18 + 16 = 34 (L) · 17 + 40 = 57 (Y) · 38 + 30 = 68 (I) · 37 + 23 = 60 (P) · 10 + 19 = 29 (C) · 15 + 36 = 51 (D) · 16 + 16 = 32 (N) · 50 + 37 = 87 (M) · 14 + 17 = 31 (F) · 45 + 33 = 78 (O) · 49 + 20 = 69 (E) · 12 + 10 = 22 (R) · 22 + 24 = 46 (H) · 18 + 36 = 54 (U) · 29 + 69 = 98 (S) · 16 + 31 = 47 (A)
- Clue 2 (Subtraction): "THE THIEF WEARS SEAWEED GOGGLES"68 - 9 = 59 (T) · 107 - 32 = 75 (E) · 67 - 23 = 44 (D) · 75 - 2 = 73 (G) · 68 - 34 = 34 (W) · 48 - 16 = 32 (A) · 61 - 11 = 50 (I) · 89 - 28 = 61 (O) · 35 - 21 = 14 (F) · 92 - 13 = 79 (H) · 84 - 6 = 78 (L) · 114 - 34 = 80 (R) · 75 - 28 = 47 (S)
- Clue 3 (Skip counting): "THE THIEF YELLS IF YOU TICKLE THEM"Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, ___, 60, 65 = 55 (T) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, ___, 30, 33 = 27 (K) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, ___, 16, 18 = 14 (O) · Skip-count by 3s. Fill the blank: 3, 6, ___, 12, 15 = 9 (Y) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, ___, 45, 50 = 40 (L) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, ___, 39, 42 = 36 (H) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, ___, 24, 27 = 21 (S) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, ___, 35, 40 = 30 (I) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, ___, 130, 140 = 120 (U) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, ___, 22, 24 = 20 (C) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, ___, 70, 75 = 65 (E) · Skip-count by 2s. Fill the blank: 2, 4, ___, 8, 10 = 6 (M) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, ___, 18, 20 = 16 (F)
- Clue 4 (Place value): "WE FOUND A SHINY BLUE SCALE"What number has 3 tens and 7 ones? = 37 (W) · What number has 5 tens and 6 ones? = 56 (L) · What number has 3 tens and 6 ones? = 36 (C) · What number has 5 tens and 5 ones? = 55 (N) · What number has 6 tens and 6 ones? = 66 (H) · What number has 6 tens and 2 ones? = 62 (D) · What number has 6 tens and 3 ones? = 63 (U) · What number has 8 tens and 4 ones? = 84 (O) · What number has 8 tens and 8 ones? = 88 (A) · What number has 1 ten and 8 ones? = 18 (I) · What number has 1 ten and 1 one? = 11 (Y) · What number has 4 tens and 3 ones? = 43 (F) · What number has 9 tens and 7 ones? = 97 (B) · What number has 8 tens and 9 ones? = 89 (S) · What number has 8 tens and 7 ones? = 87 (E)
- Clue 5 (Missing addends): surviving statement (box 2) → Ocean4 + ___ = 13 = 9 · 8 + ___ = 18 = 10 · 9 + ___ = 13 = 4 · 1 + ___ = 4 = 3 · 5 + ___ = 13 = 8 · 8 + ___ = 13 = 5 · 7 + ___ = 18 = 11 · 8 + ___ = 14 = 6 · 3 + ___ = 10 = 7 · 3 + ___ = 4 = 1 · 9 + ___ = 21 = 12
About this mystery
- Grade level
- Grade 2 math
- Math topics
- Addition, Subtraction, Skip counting, Place value, Missing addends
- Reading level
- grades 1-2
- Theme
- The Magic Pearl Mystery — set in Coral Cove
- Format
- Interactive online & printable worksheet with answer key
- Solution
- One unique, verified culprit among 21 suspects