Grade 2Reading: grades 1-2Skip countingAdditionSubtractionMultiplicationMissing addends
The Secret Island Mystery
The Golden Coconut is gone from the Treehouse Club! The Pineapple Bandit left a trail of clues deep in the jungle. We need to crack the codes and find who took it!
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 | Special Gear | Map Skills | Dominant Hand | Headwear or Hair | Fear |
|---|---|---|---|---|---|
| Dan | bubble shield | swamp jumping | right handed | green bandana | silly jokes |
| Dot | laser flashlight | cave diving | left handed | blue cap | loud whistles |
| Lily | bubble shield | river rafting | right handed | red hair | silly jokes |
| Amy | sticky boots | jungle climbing | left handed | green bandana | bright lights |
| Sam | sticky boots | bridge crossing | right handed | green bandana | loud whistles |
| Pip | laser flashlight | river rafting | right handed | blue cap | loud whistles |
| Ben | laser flashlight | jungle climbing | right handed | green bandana | silly jokes |
| Mia | grappling hook | swamp jumping | right handed | red hair | loud whistles |
| Ned | bubble shield | bridge crossing | left handed | red hair | bright lights |
| Eli | grappling hook | bridge crossing | right handed | red hair | bright lights |
| Rex | sticky boots | bridge crossing | right handed | green bandana | silly jokes |
| Toby | bubble shield | cave diving | right handed | green bandana | silly jokes |
| Joy | laser flashlight | river rafting | left handed | blue cap | silly jokes |
| Ella | super glider | swamp jumping | right handed | green bandana | silly jokes |
| Finn | sticky boots | bridge crossing | right handed | blue cap | loud whistles |
| Jake | laser flashlight | swamp jumping | right handed | red hair | silly jokes |
| Leo | laser flashlight | jungle climbing | right handed | green bandana | loud whistles |
| Luke | super glider | swamp jumping | left handed | blue cap | loud whistles |
| Gus | grappling hook | swamp jumping | right handed | blue cap | loud whistles |
| Zoe | super glider | cave diving | right handed | red hair | loud whistles |
| Abby | grappling hook | river rafting | left handed | green bandana | silly jokes |
Clue 1
Skip counting
We find a trail of muddy boots. We count them by twos to follow the path.
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
120
25
9
20
140
33
45
70
T
120
45
90
9
35
33
90
T
120
55
140
110
9
45
70
110
9
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, ___, 130, 140T
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, ___, 100, 110O
Skip-count by 5s. Fill the blank: 5, 10, 15, ___, 25, 30B
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, ___, 150, 160A
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, ___, 120, 130V
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, ___, 30, 35H
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, ___, 36, 39N
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, ___, 50, 55D
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, ___, 75, 80I
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, ___, 60, 65C
Skip-count by 3s. Fill the blank: 3, 6, ___, 12, 15E
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, ___, 40, 45S
0/12 letters found
Clue 2
Addition
We find a stash of map pieces. We add them together to see the whole map.
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
98
65
78
90
79
64
65
T
98
65
35
81
82
91
90
79
81
T
98
38
35
73
25
81
T
98
65
78
38
35
93
93
35 + 63 =T
26 + 12 =W
26 + 39 =H
29 + 62 =P
27 + 46 =S
20 + 44 =G
28 + 51 =I
35 + 46 =N
60 + 30 =R
7 + 18 =O
41 + 37 =E
50 + 32 =D
22 + 13 =A
39 + 54 =L
0/14 letters found
Clue 3
Subtraction
The bandit dropped some gold coins. We take away the fake coins to count the real ones.
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
87
63
56
43
26
58
51
27
T
87
61
26
32
86
63
56
51
26
T
87
26
64
34
67
56
107 - 20 =T
45 - 19 =A
83 - 19 =J
49 - 15 =O
91 - 33 =N
90 - 23 =K
80 - 37 =B
98 - 12 =G
98 - 37 =L
52 - 25 =I
103 - 40 =H
61 - 5 =E
54 - 3 =D
61 - 29 =U
0/14 letters found
Clue 4
Multiplication facts (1-12)
We see boxes of sweet pineapples in rows. We multiply the rows to count the fruit.
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
72
77
64
56
56
121
14
A
72
121
110
A
72
121
A
72
12
121
A
72
77
77
56
110
3
121
A
72
120
16
3
64
121
12 × 6 =A
12 × 1 =S
11 × 11 =N
2 × 8 =H
7 × 2 =B
7 × 11 =G
1 × 3 =O
10 × 12 =T
11 × 10 =D
8 × 7 =E
8 × 8 =R
0/11 letters found
Clue 5
Missing addends — the last clue
We need ten keys to unlock the chest. We have some keys and must find the rest.
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
3 + ___ = 13
2 + ___ = 6
1 + ___ = 8
6 + ___ = 17
4 + ___ = 10
9 + ___ = 17
8 + ___ = 13
7 + ___ = 10
1 + ___ = 10
3 + ___ = 15
10 + ___ = 11
Step 2 — cross out the sentence with each answer
1.The villain zoomed off the cliff, then crossed the shaky rope bridge.
2.The villain blocked the mud balls, then leaped over the muddy swamp.
3.The villain zoomed off the cliff, then swam into the dark cavern.
4.The villain walked up a steep wall, then crossed the shaky rope bridge.
5.The villain shined a bright light, then leaped over the muddy swamp.
6.The villain swung on a vine, then leaped over the muddy swamp.
7.The villain zoomed off the cliff, then leaped over the muddy swamp.
8.The villain walked up a steep wall, then splashed down the rushing river.
9.The villain blocked the mud balls, then splashed down the rushing river.
10.The villain shined a bright light, then climbed up the tall palm tree.
11.The villain blocked the mud balls, then crossed the shaky rope bridge.
12.The villain zoomed off the cliff, then climbed up the tall palm tree.
Solve it
Name the culprit
Choose the one suspect left standing.
Answer Key — The Secret Island Mystery
Culprit: Dan (bubble shield · swamp jumping · right handed · green bandana · silly jokes)
- Clue 1 (Skip counting): "THE BANDIT DOES NOT CAVE DIVE"Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, ___, 130, 140 = 120 (T) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, ___, 100, 110 = 90 (O) · Skip-count by 5s. Fill the blank: 5, 10, 15, ___, 25, 30 = 20 (B) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, ___, 150, 160 = 140 (A) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, ___, 120, 130 = 110 (V) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, ___, 30, 35 = 25 (H) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, ___, 36, 39 = 33 (N) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, ___, 50, 55 = 45 (D) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, ___, 75, 80 = 70 (I) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, ___, 60, 65 = 55 (C) · Skip-count by 3s. Fill the blank: 3, 6, ___, 12, 15 = 9 (E) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, ___, 40, 45 = 35 (S)
- Clue 2 (Addition): "THE RIGHT HANDPRINT WAS ON THE WALL"35 + 63 = 98 (T) · 26 + 12 = 38 (W) · 26 + 39 = 65 (H) · 29 + 62 = 91 (P) · 27 + 46 = 73 (S) · 20 + 44 = 64 (G) · 28 + 51 = 79 (I) · 35 + 46 = 81 (N) · 60 + 30 = 90 (R) · 7 + 18 = 25 (O) · 41 + 37 = 78 (E) · 50 + 32 = 82 (D) · 22 + 13 = 35 (A) · 39 + 54 = 93 (L)
- Clue 3 (Subtraction): "THE BANDIT LAUGHED AT A JOKE"107 - 20 = 87 (T) · 45 - 19 = 26 (A) · 83 - 19 = 64 (J) · 49 - 15 = 34 (O) · 91 - 33 = 58 (N) · 90 - 23 = 67 (K) · 80 - 37 = 43 (B) · 98 - 12 = 86 (G) · 98 - 37 = 61 (L) · 52 - 25 = 27 (I) · 103 - 40 = 63 (H) · 61 - 5 = 56 (E) · 54 - 3 = 51 (D) · 61 - 29 = 32 (U)
- Clue 4 (Multiplication facts (1-12)): "A GREEN BANDANA SNAGGED ON A THORN"12 × 6 = 72 (A) · 12 × 1 = 12 (S) · 11 × 11 = 121 (N) · 2 × 8 = 16 (H) · 7 × 2 = 14 (B) · 7 × 11 = 77 (G) · 1 × 3 = 3 (O) · 10 × 12 = 120 (T) · 11 × 10 = 110 (D) · 8 × 7 = 56 (E) · 8 × 8 = 64 (R)
- Clue 5 (Missing addends): surviving statement (box 2) → Dan3 + ___ = 13 = 10 · 2 + ___ = 6 = 4 · 1 + ___ = 8 = 7 · 6 + ___ = 17 = 11 · 4 + ___ = 10 = 6 · 9 + ___ = 17 = 8 · 8 + ___ = 13 = 5 · 7 + ___ = 10 = 3 · 1 + ___ = 10 = 9 · 3 + ___ = 15 = 12 · 10 + ___ = 11 = 1
About this mystery
- Grade level
- Grade 2 math
- Math topics
- Skip counting, Addition, Subtraction, Multiplication, Missing addends
- Reading level
- grades 1-2
- Theme
- The Secret Island Mystery — set in Skull Rock Jungle
- Format
- Interactive online & printable worksheet with answer key
- Solution
- One unique, verified culprit among 21 suspects