🦕 DinosaursGrade 2Reading: grades 3-4AdditionPlace valueSubtractionSkip countingMissing addends
The Golden Triceratops Caper
A sneaky thief has swiped the priceless Golden Triceratops Skull! The Dino Valley team needs your help to find the culprit before they escape the dig site.
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 | Favorite Fossil Tool | Dino Companion | Dominant Hand | Safety Helmet Color | Silly Fear |
|---|---|---|---|---|---|
| Dong Zhiming | Dusting Brush | Stegosaurus Calf | Left Handed | Red Helmet | Flashlight Beams |
| Steve Brusatte | Rock Pick | T Rex Hatchling | Right Handed | Blue Helmet | Loud Sneezes |
| Sue Hendrickson | Dusting Brush | Triceratops Baby | Left Handed | Blue Helmet | Squeaky Toys |
| Robert Bakker | Magnifying Glass | Pterodactyl Chick | Right Handed | Red Helmet | Squeaky Toys |
| Jack Horner | Plaster Wrap | Velociraptor Pup | Left Handed | Red Helmet | Flashlight Beams |
| Danny Dino | Rock Pick | Triceratops Baby | Left Handed | Red Helmet | Flashlight Beams |
| Patricia Vickers | Rock Pick | Stegosaurus Calf | Left Handed | Blue Helmet | Squeaky Toys |
| Roxy Raptor | Rock Pick | T Rex Hatchling | Right Handed | Yellow Helmet | Flashlight Beams |
| Luis Alvarez | Magnifying Glass | T Rex Hatchling | Left Handed | Yellow Helmet | Loud Sneezes |
| Joan Wiffen | Rock Pick | Velociraptor Pup | Left Handed | Red Helmet | Squeaky Toys |
| Alan Grant | Chisel Hammer | Velociraptor Pup | Right Handed | Red Helmet | Loud Sneezes |
| Gideon Mantell | Dusting Brush | Pterodactyl Chick | Left Handed | Red Helmet | Squeaky Toys |
| Karen Chin | Magnifying Glass | Triceratops Baby | Left Handed | Red Helmet | Flashlight Beams |
| Paul Sereno | Magnifying Glass | Triceratops Baby | Left Handed | Red Helmet | Squeaky Toys |
| Rex Stone | Magnifying Glass | Velociraptor Pup | Left Handed | Blue Helmet | Loud Sneezes |
| Charles Marsh | Dusting Brush | Velociraptor Pup | Left Handed | Red Helmet | Squeaky Toys |
| Barnum Brown | Magnifying Glass | Velociraptor Pup | Right Handed | Blue Helmet | Loud Sneezes |
| Mary Anning | Plaster Wrap | Triceratops Baby | Right Handed | Blue Helmet | Squeaky Toys |
| Zofia Kielan | Plaster Wrap | T Rex Hatchling | Left Handed | Red Helmet | Squeaky Toys |
| Edward Cope | Dusting Brush | Triceratops Baby | Left Handed | Blue Helmet | Flashlight Beams |
| Ellie Sattler | Magnifying Glass | Velociraptor Pup | Left Handed | Yellow Helmet | Squeaky Toys |
Clue 1
Addition
Ranger Parker counted twenty-four raptor claws in one box and fifteen in another to unlock this clue.
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
92
74
83
T
92
74
28
83
55
38
33
83
24
47
33
T
92
74
34
26
83
34
49
34
49
39
T
92
72
28
88
83
72
34
T
92
33
45
24
50 + 42 =T
24 + 23 =N
20 + 29 =B
41 + 47 =C
27 + 12 =Y
27 + 28 =F
10 + 18 =I
8 + 18 =V
42 + 30 =R
23 + 15 =D
13 + 11 =S
27 + 56 =E
19 + 15 =A
44 + 30 =H
14 + 19 =O
17 + 28 =P
0/16 letters found
Clue 2
Place value
To read the map coordinates, the team had to figure out the value of the digit in the tens place.
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
93
22
99
15
92
99
45
T
93
86
92
99
45
T
93
22
86
68
38
99
38
T
93
21
21
92
81
31
11
68
T
93
What number has 9 tens and 3 ones?T
What number has 8 tens and 6 ones?A
What number has 1 ten and 5 ones?Y
What number has 3 tens and 8 ones?D
What number has 2 tens and 2 ones?H
What number has 8 tens and 1 one?P
What number has 6 tens and 8 ones?N
What number has 4 tens and 5 ones?F
What number has 9 tens and 9 ones?E
What number has 3 tens and 1 one?R
What number has 1 ten and 1 one?I
What number has 9 tens and 2 ones?L
What number has 2 tens and 1 one?O
0/13 letters found
Clue 3
Subtraction
We found the clue after subtracting the broken fossil brushes from our total 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.
T
79
49
72
T
79
49
51
72
68
64
22
27
22
58
22
19
68
64
20
81
14
62
45
72
22
55
19
T
79
20
19
14
96 - 17 =T
83 - 25 =W
26 - 7 =Y
90 - 35 =K
72 - 23 =H
84 - 22 =Q
101 - 20 =M
24 - 10 =S
76 - 12 =R
48 - 26 =A
50 - 5 =U
81 - 13 =F
55 - 35 =O
80 - 29 =I
36 - 9 =N
81 - 9 =E
0/16 letters found
Clue 4
Skip counting
The footprints went deep into the swamp, and counting them by fives led us to a hidden note.
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
100
130
22
8
140
22
25
90
22
26
40
26
130
A
100
10
27
A
100
40
25
22
21
26
50
22
140
12
28
8
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, ___, 110, 120A
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, ___, 45, 50S
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, ___, 12, 14P
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, ___, 140, 150R
Skip-count by 2s. Fill the blank: 2, 4, 6, ___, 10, 12D
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, ___, 24, 27F
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, ___, 30, 33W
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, ___, 24, 26E
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, ___, 28, 30T
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, ___, 100, 110M
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, ___, 30, 32N
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, ___, 150, 160H
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, ___, 60, 70B
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, ___, 30, 35L
Skip-count by 3s. Fill the blank: 3, 6, 9, ___, 15, 18I
0/15 letters found
Clue 5
Missing addends — the last clue
We knew we needed twelve secure crates, but only had eight. Finding the missing amount gave us the final lead.
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
1 + ___ = 6
7 + ___ = 18
3 + ___ = 13
6 + ___ = 10
6 + ___ = 18
4 + ___ = 11
10 + ___ = 16
1 + ___ = 3
10 + ___ = 19
4 + ___ = 7
8 + ___ = 16
Step 2 — cross out the sentence with each answer
1.The villain crept through the dusty canyon, then hid the prize in a dusty backpack.
2.The villain dug up the fossil bed, then paddled down the muddy river.
3.The villain dug up the fossil bed, then dashed into the fern forest.
4.The villain unlocked the secure display case, then zipped away on an electric cart.
5.The villain sneaked past the sleeping t-rex, then dashed into the fern forest.
6.The villain unlocked the secure display case, then jumped onto a roaring dirt bike.
7.The villain dug up the fossil bed, then jumped onto a roaring dirt bike.
8.The villain unlocked the secure display case, then dashed into the fern forest.
9.The villain crept through the dusty canyon, then zipped away on an electric cart.
10.The villain scrambled over the safety fence, then jumped onto a roaring dirt bike.
11.The villain sneaked past the sleeping t-rex, then hid the prize in a dusty backpack.
12.The villain scrambled over the safety fence, then dashed into the fern forest.
Solve it
Name the culprit
Choose the one suspect left standing.
Answer Key — The Golden Triceratops Caper
Culprit: Joan Wiffen (Rock Pick · Velociraptor Pup · Left Handed · Red Helmet · Squeaky Toys)
- Clue 1 (Addition): "THE THIEF DOES NOT HAVE A BABY TRICERATOPS"50 + 42 = 92 (T) · 24 + 23 = 47 (N) · 20 + 29 = 49 (B) · 41 + 47 = 88 (C) · 27 + 12 = 39 (Y) · 27 + 28 = 55 (F) · 10 + 18 = 28 (I) · 8 + 18 = 26 (V) · 42 + 30 = 72 (R) · 23 + 15 = 38 (D) · 13 + 11 = 24 (S) · 27 + 56 = 83 (E) · 19 + 15 = 34 (A) · 44 + 30 = 74 (H) · 14 + 19 = 33 (O) · 17 + 28 = 45 (P)
- Clue 2 (Place value): "THEY LEFT A LEFT HANDED TOOL PRINT"What number has 9 tens and 3 ones? = 93 (T) · What number has 8 tens and 6 ones? = 86 (A) · What number has 1 ten and 5 ones? = 15 (Y) · What number has 3 tens and 8 ones? = 38 (D) · What number has 2 tens and 2 ones? = 22 (H) · What number has 8 tens and 1 one? = 81 (P) · What number has 6 tens and 8 ones? = 68 (N) · What number has 4 tens and 5 ones? = 45 (F) · What number has 9 tens and 9 ones? = 99 (E) · What number has 3 tens and 1 one? = 31 (R) · What number has 1 ten and 1 one? = 11 (I) · What number has 9 tens and 2 ones? = 92 (L) · What number has 2 tens and 1 one? = 21 (O)
- Clue 3 (Subtraction): "THE THIEF RAN AWAY FROM SQUEAKY TOYS"96 - 17 = 79 (T) · 83 - 25 = 58 (W) · 26 - 7 = 19 (Y) · 90 - 35 = 55 (K) · 72 - 23 = 49 (H) · 84 - 22 = 62 (Q) · 101 - 20 = 81 (M) · 24 - 10 = 14 (S) · 76 - 12 = 64 (R) · 48 - 26 = 22 (A) · 50 - 5 = 45 (U) · 81 - 13 = 68 (F) · 55 - 35 = 20 (O) · 80 - 29 = 51 (I) · 36 - 9 = 27 (N) · 81 - 9 = 72 (E)
- Clue 4 (Skip counting): "A RED HELMET STRAP WAS LEFT BEHIND"Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, ___, 110, 120 = 100 (A) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, ___, 45, 50 = 40 (S) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, ___, 12, 14 = 10 (P) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, ___, 140, 150 = 130 (R) · Skip-count by 2s. Fill the blank: 2, 4, 6, ___, 10, 12 = 8 (D) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, ___, 24, 27 = 21 (F) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, ___, 30, 33 = 27 (W) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, ___, 24, 26 = 22 (E) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, ___, 28, 30 = 26 (T) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, ___, 100, 110 = 90 (M) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, ___, 30, 32 = 28 (N) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, ___, 150, 160 = 140 (H) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, ___, 60, 70 = 50 (B) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, ___, 30, 35 = 25 (L) · Skip-count by 3s. Fill the blank: 3, 6, 9, ___, 15, 18 = 12 (I)
- Clue 5 (Missing addends): surviving statement (box 1) → Joan Wiffen1 + ___ = 6 = 5 · 7 + ___ = 18 = 11 · 3 + ___ = 13 = 10 · 6 + ___ = 10 = 4 · 6 + ___ = 18 = 12 · 4 + ___ = 11 = 7 · 10 + ___ = 16 = 6 · 1 + ___ = 3 = 2 · 10 + ___ = 19 = 9 · 4 + ___ = 7 = 3 · 8 + ___ = 16 = 8
About this mystery
- Grade level
- Grade 2 math
- Math topics
- Addition, Place value, Subtraction, Skip counting, Missing addends
- Reading level
- grades 3-4
- Theme
- The Golden Triceratops Caper — set in Mesozoic Valley Dig Site
- Format
- Interactive online & printable worksheet with answer key
- Solution
- One unique, verified culprit among 21 suspects