🌊 MermaidsGrade 1Reading: grades 1-2AdditionSubtractionSkip countingPlace valueMissing addends
The Mystery of the Pink Pearl
Oh no! The shiny Pink Pearl is gone from Coral Cove Castle. A rogue mermaid took it. We must find them!
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 | bubble magic | ocean gear | swimming style | seaweed crown | secret fear |
|---|---|---|---|---|---|
| Storm | kelp tangling | gold crown | right handed fin | red sea-ribbon | tickly sea feather |
| Shelly | kelp tangling | sea shell map | right handed fin | green kelp | loud whale song |
| Nerida | tide twisting | gold crown | right handed fin | red sea-ribbon | tickly sea feather |
| River | kelp tangling | gold crown | right handed fin | blue sea-grass | loud whale song |
| Sandy | wave jumping | sea shell map | right handed fin | blue sea-grass | loud whale song |
| Cleo | kelp tangling | pearl ring | left handed fin | blue sea-grass | bright flashlight |
| Brooke | wave jumping | coral wand | left handed fin | red sea-ribbon | bright flashlight |
| Marina | kelp tangling | coral wand | left handed fin | red sea-ribbon | tickly sea feather |
| Ocean | wave jumping | pearl ring | right handed fin | red sea-ribbon | tickly sea feather |
| Kai | tide twisting | sea shell map | right handed fin | red sea-ribbon | tickly sea feather |
| Splash | shell singing | sea shell map | left handed fin | blue sea-grass | loud whale song |
| Ariel | star shining | pearl ring | right handed fin | red sea-ribbon | tickly sea feather |
| Pearl | kelp tangling | coral wand | right handed fin | red sea-ribbon | bright flashlight |
| Finn | shell singing | sea shell map | left handed fin | blue sea-grass | tickly sea feather |
| Ray | kelp tangling | coral wand | left handed fin | blue sea-grass | loud whale song |
| Coral | wave jumping | pink cape | right handed fin | red sea-ribbon | bright flashlight |
| Tallulah | star shining | pearl ring | right handed fin | red sea-ribbon | bright flashlight |
| Wade | wave jumping | pearl ring | right handed fin | blue sea-grass | tickly sea feather |
| Caspian | shell singing | sea shell map | left handed fin | green kelp | tickly sea feather |
| Waverly | tide twisting | coral wand | left handed fin | red sea-ribbon | loud whale song |
| Nixie | tide twisting | pink cape | right handed fin | green kelp | loud whale song |
Clue 1
Addition
We count the starfish on the sea wall. Some are red and some are blue. Let us add them all up 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
18
15
7
12
16
2
2
20
16
4
13
5
7
10
4
5
T
18
15
20
12
7
20
10
7
20
10
15
7
2
2
9
20
17
9 + 9 =T
6 + 9 =H
1 + 3 =N
1 + 1 =L
3 + 2 =O
11 + 6 =P
7 + 5 =V
4 + 6 =S
11 + 9 =A
12 + 4 =I
3 + 4 =E
2 + 7 =M
3 + 10 =D
0/13 letters found
Clue 2
Subtraction
A hungry crab ate some of our sweet kelp snacks. Let us subtract the eaten snacks to see what is left.
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
2
10
18
3
7
14
1
15
T
2
13
T
2
10
18
17
12
9
10
T
2
T
2
13
18
7
16
1
4
18
7 - 5 =T
19 - 1 =E
11 - 1 =H
11 - 7 =P
19 - 3 =C
16 - 4 =I
18 - 3 =M
8 - 1 =S
4 - 3 =A
10 - 7 =Y
15 - 2 =O
18 - 1 =R
14 - 5 =G
17 - 3 =W
0/14 letters found
Clue 3
Skip counting
We see schools of tiny fish swimming by twos. Let us count them by twos to see how many fish are in the bay.
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
20
60
120
25
28
60
140
80
120
45
120
6
110
60
120
36
12
24
120
12
T
20
60
120
45
T
20
42
100
33
60
120
6
T
20
60
120
18
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, ___, 22, 24T
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, ___, 21, 24M
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 39, ___, 45, 48O
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, ___, 130, 140E
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, ___, 50, 55R
Skip-count by 2s. Fill the blank: 2, 4, ___, 8, 10D
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, ___, 14, 16A
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, ___, 36, 39C
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, ___, 70, 80H
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, ___, 39, 42N
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, ___, 30, 32S
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, ___, 120, 130W
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, ___, 30, 35Y
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, ___, 110, 120U
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, ___, 150, 160I
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, ___, 90, 100V
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, ___, 27, 30F
0/17 letters found
Clue 4
Place value
The sea shells are packed in boxes of ten and some single shells. We must count the tens and ones to find the number.
Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.
A
53
56
36
47
56
90
78
78
38
33
45
A
53
43
60
36
62
16
90
33
16
82
36
43
A
53
33
47
What number has 5 tens and 3 ones?A
What number has 3 tens and 3 ones?N
What number has 8 tens and 2 ones?H
What number has 5 tens and 6 ones?R
What number has 6 tens and 0 ones?L
What number has 9 tens and 0 ones?I
What number has 3 tens and 6 ones?E
What number has 4 tens and 7 ones?D
What number has 6 tens and 2 ones?F
What number has 7 tens and 8 ones?B
What number has 1 ten and 6 ones?T
What number has 4 tens and 3 ones?S
What number has 3 tens and 8 ones?O
What number has 4 tens and 5 ones?W
0/14 letters found
Clue 5
Missing addends — the last clue
We need ten shiny pearls to open the magic chest, but we only have six. Let us find the missing number to open it.
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
2 + ___ = 4
3 + ___ = 13
6 + ___ = 15
5 + ___ = 17
1 + ___ = 12
6 + ___ = 14
9 + ___ = 10
5 + ___ = 8
9 + ___ = 16
10 + ___ = 14
8 + ___ = 13
Step 2 — cross out the sentence with each answer
1.The villain shines like a bright star, then polishes a heavy gold crown.
2.The villain jumps over the giant waves, then spins a magic pearl ring.
3.The villain sings a sleepy shell song, then puts on a shiny pink cape.
4.The villain twists the strong sea tides, then puts on a shiny pink cape.
5.The villain tangles the path with kelp, then checks a dusty sea shell map.
6.The villain shines like a bright star, then spins a magic pearl ring.
7.The villain sings a sleepy shell song, then checks a dusty sea shell map.
8.The villain twists the strong sea tides, then checks a dusty sea shell map.
9.The villain twists the strong sea tides, then polishes a heavy gold crown.
10.The villain tangles the path with kelp, then polishes a heavy gold crown.
11.The villain jumps over the giant waves, then puts on a shiny pink cape.
12.The villain twists the strong sea tides, then waves a glowing coral wand.
Solve it
Name the culprit
Choose the one suspect left standing.
Answer Key — The Mystery of the Pink Pearl
Culprit: Ariel (star shining · pearl ring · right handed fin · red sea-ribbon · tickly sea feather)
- Clue 1 (Addition): "THE VILLAIN DOES NOT HAVE A SEA SHELL MAP"9 + 9 = 18 (T) · 6 + 9 = 15 (H) · 1 + 3 = 4 (N) · 1 + 1 = 2 (L) · 3 + 2 = 5 (O) · 11 + 6 = 17 (P) · 7 + 5 = 12 (V) · 4 + 6 = 10 (S) · 11 + 9 = 20 (A) · 12 + 4 = 16 (I) · 3 + 4 = 7 (E) · 2 + 7 = 9 (M) · 3 + 10 = 13 (D)
- Clue 2 (Subtraction): "THEY SWAM TO THE RIGHT TO ESCAPE"7 - 5 = 2 (T) · 19 - 1 = 18 (E) · 11 - 1 = 10 (H) · 11 - 7 = 4 (P) · 19 - 3 = 16 (C) · 16 - 4 = 12 (I) · 18 - 3 = 15 (M) · 8 - 1 = 7 (S) · 4 - 3 = 1 (A) · 10 - 7 = 3 (Y) · 15 - 2 = 13 (O) · 18 - 1 = 17 (R) · 14 - 5 = 9 (G) · 17 - 3 = 14 (W)
- Clue 3 (Skip counting): "THEY SHIVERED WHEN A FEATHER TOUCHED THEM"Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, ___, 22, 24 = 20 (T) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, ___, 21, 24 = 18 (M) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 39, ___, 45, 48 = 42 (O) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, ___, 130, 140 = 120 (E) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, ___, 50, 55 = 45 (R) · Skip-count by 2s. Fill the blank: 2, 4, ___, 8, 10 = 6 (D) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, ___, 14, 16 = 12 (A) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, ___, 36, 39 = 33 (C) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, ___, 70, 80 = 60 (H) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, ___, 39, 42 = 36 (N) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, ___, 30, 32 = 28 (S) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, ___, 120, 130 = 110 (W) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, ___, 30, 35 = 25 (Y) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, ___, 110, 120 = 100 (U) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, ___, 150, 160 = 140 (I) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, ___, 90, 100 = 80 (V) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, ___, 27, 30 = 24 (F)
- Clue 4 (Place value): "A RED RIBBON WAS LEFT IN THE SAND"What number has 5 tens and 3 ones? = 53 (A) · What number has 3 tens and 3 ones? = 33 (N) · What number has 8 tens and 2 ones? = 82 (H) · What number has 5 tens and 6 ones? = 56 (R) · What number has 6 tens and 0 ones? = 60 (L) · What number has 9 tens and 0 ones? = 90 (I) · What number has 3 tens and 6 ones? = 36 (E) · What number has 4 tens and 7 ones? = 47 (D) · What number has 6 tens and 2 ones? = 62 (F) · What number has 7 tens and 8 ones? = 78 (B) · What number has 1 ten and 6 ones? = 16 (T) · What number has 4 tens and 3 ones? = 43 (S) · What number has 3 tens and 8 ones? = 38 (O) · What number has 4 tens and 5 ones? = 45 (W)
- Clue 5 (Missing addends): surviving statement (box 6) → Ariel2 + ___ = 4 = 2 · 3 + ___ = 13 = 10 · 6 + ___ = 15 = 9 · 5 + ___ = 17 = 12 · 1 + ___ = 12 = 11 · 6 + ___ = 14 = 8 · 9 + ___ = 10 = 1 · 5 + ___ = 8 = 3 · 9 + ___ = 16 = 7 · 10 + ___ = 14 = 4 · 8 + ___ = 13 = 5
About this mystery
- Grade level
- Grade 1 math
- Math topics
- Addition, Subtraction, Skip counting, Place value, Missing addends
- Reading level
- grades 1-2
- Theme
- The Mystery of the Pink Pearl — set in Coral Cove Castle
- Format
- Interactive online & printable worksheet with answer key
- Solution
- One unique, verified culprit among 21 suspects