Grade 2Reading: grades 7-9Place valueAdditionSubtractionSkip countingMissing addends
The Serpent Ridge Sabotage
A masked figure compromised the expedition base camp at Serpent Ridge Ruins, disabling security field arrays and snatching sensitive ancient survey maps. Detective scouts must analyze field telemetry and track down the suspect before the rogue escapes the perimeter.
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 | Infiltration Skill | Field Gear | Wrist Compass | Hairstyle | Sensory Vulnerability |
|---|---|---|---|---|---|
| Cartographer Iris | Sonic Whistle | Machete Blade | Right Wrist Compass | Wild Dreadlocks | High Pitch Whistle |
| Ranger Mateo | Trap Disarming | Machete Blade | Left Wrist Compass | Buzz Cut | Bright Flashlight |
| Surveyor Nora | Paraglider Flight | Smoke Bombs | Left Wrist Compass | Buzz Cut | Citrus Smoke |
| Ranger Jax | Sonic Whistle | Smoke Bombs | Left Wrist Compass | Buzz Cut | Bright Flashlight |
| Officer Diaz | Sonic Whistle | Night Goggles | Left Wrist Compass | Buzz Cut | Bright Flashlight |
| Scout Elena | Sonic Whistle | Machete Blade | Right Wrist Compass | Buzz Cut | Bright Flashlight |
| Professor Chen | Stealth Cloaking | Night Goggles | Left Wrist Compass | Braided Ponytail | Bright Flashlight |
| Specialist Flynn | Sonic Whistle | Smoke Bombs | Right Wrist Compass | Braided Ponytail | High Pitch Whistle |
| Analyst Quinn | Paraglider Flight | Grappling Hook | Left Wrist Compass | Braided Ponytail | High Pitch Whistle |
| Captain Vance | Trap Disarming | Signal Flares | Right Wrist Compass | Wild Dreadlocks | Bright Flashlight |
| Commander Cross | Stealth Cloaking | Smoke Bombs | Left Wrist Compass | Braided Ponytail | Bright Flashlight |
| Agent Sterling | Venom Darting | Night Goggles | Left Wrist Compass | Braided Ponytail | Bright Flashlight |
| Agent Reed | Trap Disarming | Grappling Hook | Left Wrist Compass | Buzz Cut | Bright Flashlight |
| Warden Blake | Trap Disarming | Night Goggles | Left Wrist Compass | Buzz Cut | Bright Flashlight |
| Engineer Omar | Paraglider Flight | Night Goggles | Right Wrist Compass | Buzz Cut | Bright Flashlight |
| Pilot Thorne | Paraglider Flight | Grappling Hook | Left Wrist Compass | Wild Dreadlocks | Citrus Smoke |
| Explorer Brock | Sonic Whistle | Grappling Hook | Left Wrist Compass | Braided Ponytail | High Pitch Whistle |
| Archivist Kim | Trap Disarming | Smoke Bombs | Left Wrist Compass | Wild Dreadlocks | Bright Flashlight |
| Tracker Maya | Venom Darting | Smoke Bombs | Left Wrist Compass | Wild Dreadlocks | Citrus Smoke |
| Navigator Sam | Stealth Cloaking | Smoke Bombs | Right Wrist Compass | Buzz Cut | Bright Flashlight |
| Scout Harper | Paraglider Flight | Smoke Bombs | Left Wrist Compass | Wild Dreadlocks | Bright Flashlight |
Clue 1
Place value
At the jungle ruins entry, the digital security console displays digit positions to verify team credentials.
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
67
28
40
57
66
92
92
54
66
50
32
30
40
84
50
30
T
67
87
84
40
54
14
15
54
11
11
92
66
50
14
28
30
30
98
What number has 6 tens and 7 ones?T
What number has 8 tens and 7 ones?U
What number has 9 tens and 2 ones?L
What number has 8 tens and 4 ones?S
What number has 9 tens and 8 ones?K
What number has 1 ten and 4 ones?G
What number has 4 tens and 0 ones?E
What number has 6 tens and 6 ones?I
What number has 1 ten and 5 ones?R
What number has 2 tens and 8 ones?H
What number has 5 tens and 4 ones?A
What number has 5 tens and 7 ones?V
What number has 3 tens and 2 ones?D
What number has 3 tens and 0 ones?O
What number has 1 ten and 1 one?P
What number has 5 tens and 0 ones?N
0/16 letters found
Clue 2
Addition
To cross the flooded ravine, the scouts tally supply packs from both canoes to balance weight.
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
51
50
41
91
69
24
62
98
42
T
51
21
41
77
98
88
77
91
35
54
62
77
88
88
35
26
24
41
23
T
51
21
98
42
88
T
51
33 + 18 =T
47 + 22 =U
15 + 8 =F
14 + 12 =N
20 + 15 =O
34 + 28 =P
36 + 62 =R
12 + 9 =W
21 + 20 =E
35 + 56 =C
25 + 17 =I
28 + 26 =M
59 + 29 =S
27 + 23 =H
39 + 38 =A
16 + 8 =L
0/16 letters found
Clue 3
Subtraction
Inside the ancient temple, the team calculates remaining battery power by subtracting energy consumed.
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
24
58
36
48
16
36
21
49
14
36
13
83
37
31
36
59
22
14
83
86
21
28
14
37
64
58
T
24
22
31
21
48
58
31
37
64
58
T
24
42 - 18 =T
107 - 21 =M
32 - 4 =B
26 - 12 =R
45 - 9 =E
44 - 13 =L
45 - 23 =F
84 - 26 =H
91 - 27 =G
93 - 10 =O
69 - 10 =D
42 - 26 =N
28 - 15 =C
85 - 37 =S
36 - 15 =A
68 - 19 =K
52 - 15 =I
0/17 letters found
Clue 4
Skip counting
Navigating the stone rope bridges requires stepping across marked tiles in regular skip patterns.
Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.
D
50
9
15
9
30
15
27
20
9
25
40
65
26
90
D
50
25
22
65
70
15
55
26
100
100
30
26
15
22
39
27
70
25
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, ___, 55, 60D
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, ___, 30, 33I
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, ___, 30, 35S
Skip-count by 5s. Fill the blank: 5, 10, ___, 20, 25T
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, ___, 33, 36C
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, ___, 70, 75O
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, ___, 42, 45A
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, ___, 60, 65B
Skip-count by 3s. Fill the blank: 3, 6, ___, 12, 15E
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, ___, 24, 26H
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, ___, 110, 120Z
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, ___, 80, 90R
Skip-count by 5s. Fill the blank: 5, 10, 15, ___, 25, 30V
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, ___, 100, 110N
Skip-count by 10s. Fill the blank: 10, 20, 30, ___, 50, 60F
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, ___, 28, 30U
0/16 letters found
Clue 5
Missing addends — the last clue
Unlocking the inner sanctuary door requires finding the exact missing code number for the stone dial.
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 + ___ = 6
10 + ___ = 17
2 + ___ = 11
4 + ___ = 12
10 + ___ = 15
3 + ___ = 6
5 + ___ = 9
9 + ___ = 10
10 + ___ = 22
2 + ___ = 13
2 + ___ = 8
Step 2 — cross out the sentence with each answer
1.The villain activated stealth cloaking, then tossed a smoke bomb.
2.The villain blew a sonic whistle, then tossed a smoke bomb.
3.The villain deployed paraglider flight, then swung a machete blade.
4.The villain activated stealth cloaking, then swung a machete blade.
5.The villain activated stealth cloaking, then fired a signal flare.
6.The villain deployed paraglider flight, then adjusted night goggles.
7.The villain disarmed a pressure trap, then adjusted night goggles.
8.The villain disarmed a pressure trap, then tossed a smoke bomb.
9.The villain blew a sonic whistle, then adjusted night goggles.
10.The villain disarmed a pressure trap, then swung a machete blade.
11.The villain fired a venom dart, then tossed a smoke bomb.
12.The villain fired a venom dart, then launched a grappling hook.
Solve it
Name the culprit
Choose the one suspect left standing.
Answer Key — The Serpent Ridge Sabotage
Culprit: Ranger Mateo (Trap Disarming · Machete Blade · Left Wrist Compass · Buzz Cut · Bright Flashlight)
- Clue 1 (Place value): "THE VILLAIN DOES NOT USE A GRAPPLING HOOK"What number has 6 tens and 7 ones? = 67 (T) · What number has 8 tens and 7 ones? = 87 (U) · What number has 9 tens and 2 ones? = 92 (L) · What number has 8 tens and 4 ones? = 84 (S) · What number has 9 tens and 8 ones? = 98 (K) · What number has 1 ten and 4 ones? = 14 (G) · What number has 4 tens and 0 ones? = 40 (E) · What number has 6 tens and 6 ones? = 66 (I) · What number has 1 ten and 5 ones? = 15 (R) · What number has 2 tens and 8 ones? = 28 (H) · What number has 5 tens and 4 ones? = 54 (A) · What number has 5 tens and 7 ones? = 57 (V) · What number has 3 tens and 2 ones? = 32 (D) · What number has 3 tens and 0 ones? = 30 (O) · What number has 1 ten and 1 one? = 11 (P) · What number has 5 tens and 0 ones? = 50 (N)
- Clue 2 (Addition): "THE CULPRIT WEARS A COMPASS ON LEFT WRIST"33 + 18 = 51 (T) · 47 + 22 = 69 (U) · 15 + 8 = 23 (F) · 14 + 12 = 26 (N) · 20 + 15 = 35 (O) · 34 + 28 = 62 (P) · 36 + 62 = 98 (R) · 12 + 9 = 21 (W) · 21 + 20 = 41 (E) · 35 + 56 = 91 (C) · 25 + 17 = 42 (I) · 28 + 26 = 54 (M) · 59 + 29 = 88 (S) · 27 + 23 = 50 (H) · 39 + 38 = 77 (A) · 16 + 8 = 24 (L)
- Clue 3 (Subtraction): "THE SNEAK RECOILED FROM A BRIGHT FLASHLIGHT"42 - 18 = 24 (T) · 107 - 21 = 86 (M) · 32 - 4 = 28 (B) · 26 - 12 = 14 (R) · 45 - 9 = 36 (E) · 44 - 13 = 31 (L) · 45 - 23 = 22 (F) · 84 - 26 = 58 (H) · 91 - 27 = 64 (G) · 93 - 10 = 83 (O) · 69 - 10 = 59 (D) · 42 - 26 = 16 (N) · 28 - 15 = 13 (C) · 85 - 37 = 48 (S) · 36 - 15 = 21 (A) · 68 - 19 = 49 (K) · 52 - 15 = 37 (I)
- Clue 4 (Skip counting): "DETECTIVES FOUND SHORT BUZZ CUT HAIRS"Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, ___, 55, 60 = 50 (D) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, ___, 30, 33 = 27 (I) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, ___, 30, 35 = 25 (S) · Skip-count by 5s. Fill the blank: 5, 10, ___, 20, 25 = 15 (T) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, ___, 33, 36 = 30 (C) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, ___, 70, 75 = 65 (O) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, ___, 42, 45 = 39 (A) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, ___, 60, 65 = 55 (B) · Skip-count by 3s. Fill the blank: 3, 6, ___, 12, 15 = 9 (E) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, ___, 24, 26 = 22 (H) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, ___, 110, 120 = 100 (Z) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, ___, 80, 90 = 70 (R) · Skip-count by 5s. Fill the blank: 5, 10, 15, ___, 25, 30 = 20 (V) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, ___, 100, 110 = 90 (N) · Skip-count by 10s. Fill the blank: 10, 20, 30, ___, 50, 60 = 40 (F) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, ___, 28, 30 = 26 (U)
- Clue 5 (Missing addends): surviving statement (box 10) → Ranger Mateo4 + ___ = 6 = 2 · 10 + ___ = 17 = 7 · 2 + ___ = 11 = 9 · 4 + ___ = 12 = 8 · 10 + ___ = 15 = 5 · 3 + ___ = 6 = 3 · 5 + ___ = 9 = 4 · 9 + ___ = 10 = 1 · 10 + ___ = 22 = 12 · 2 + ___ = 13 = 11 · 2 + ___ = 8 = 6
About this mystery
- Grade level
- Grade 2 math
- Math topics
- Place value, Addition, Subtraction, Skip counting, Missing addends
- Reading level
- grades 7-9
- Theme
- The Serpent Ridge Sabotage — set in Serpent Ridge Jungle Ruins
- Format
- Interactive online & printable worksheet with answer key
- Solution
- One unique, verified culprit among 21 suspects