🦕 DinosaursGrade 1Reading: grades 1-2Place valueAdditionSubtractionSkip countingMissing addends
The Case of the Roaring Dino
A sneaky dinosaur scrambled through Dino Valley and took the glowing golden fossil! Help Ranger Rick read the clue notes and solve the mystery!
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 | Dino Power | Special Trait | Footprint | Head Crest | Scared By |
|---|---|---|---|---|---|
| Gideon | Ankylosaurus Armor | Giant Wings | Left Footed Prints | Spiky Frill | Loud Whistle |
| Sam | T Rex Roar | Camouflage Skin | Right Footed Prints | Spiky Frill | Loud Whistle |
| Stan | T Rex Roar | Camouflage Skin | Right Footed Prints | Smooth Ridge | Loud Whistle |
| Mantell | Ankylosaurus Armor | Mud Digging | Left Footed Prints | Spiky Frill | Loud Whistle |
| Cliff | Triceratops Charge | Camouflage Skin | Right Footed Prints | Smooth Ridge | Loud Whistle |
| Amber | Stegosaurus Tail Whip | Giant Wings | Left Footed Prints | Feather Crest | Bright Flashlight |
| Spike | Stegosaurus Tail Whip | Camouflage Skin | Left Footed Prints | Feather Crest | Loud Whistle |
| Mary | Raptor Dash | Night Vision | Left Footed Prints | Spiky Frill | Loud Whistle |
| Penny | Triceratops Charge | Lava Immunity | Left Footed Prints | Smooth Ridge | Loud Whistle |
| Rocky | T Rex Roar | Lava Immunity | Left Footed Prints | Feather Crest | Squeaky Toy |
| Scotty | Triceratops Charge | Camouflage Skin | Right Footed Prints | Smooth Ridge | Squeaky Toy |
| Flint | Raptor Dash | Mud Digging | Left Footed Prints | Spiky Frill | Squeaky Toy |
| Tristan | Ankylosaurus Armor | Lava Immunity | Left Footed Prints | Feather Crest | Loud Whistle |
| Anning | Raptor Dash | Mud Digging | Left Footed Prints | Feather Crest | Loud Whistle |
| Daisy | Ankylosaurus Armor | Giant Wings | Right Footed Prints | Feather Crest | Loud Whistle |
| Bones | Stegosaurus Tail Whip | Mud Digging | Right Footed Prints | Spiky Frill | Squeaky Toy |
| Barnum | T Rex Roar | Mud Digging | Left Footed Prints | Feather Crest | Bright Flashlight |
| Dusty | Ankylosaurus Armor | Night Vision | Left Footed Prints | Feather Crest | Loud Whistle |
| Charlie | Raptor Dash | Mud Digging | Left Footed Prints | Smooth Ridge | Loud Whistle |
| Echo | T Rex Roar | Camouflage Skin | Left Footed Prints | Spiky Frill | Bright Flashlight |
| Clover | Triceratops Charge | Giant Wings | Left Footed Prints | Feather Crest | Loud Whistle |
Clue 1
Place value
You check the digit counters on the lab door lock to decode a 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
14
51
22
93
89
33
33
42
89
77
23
65
22
94
77
65
T
14
51
42
93
22
33
42
93
42
89
70
70
74
77
89
T
14
45
What number has 1 ten and 4 ones?T
What number has 4 tens and 5 ones?Y
What number has 7 tens and 7 ones?N
What number has 7 tens and 0 ones?M
What number has 7 tens and 4 ones?U
What number has 9 tens and 3 ones?V
What number has 2 tens and 3 ones?D
What number has 3 tens and 3 ones?L
What number has 6 tens and 5 ones?O
What number has 4 tens and 2 ones?A
What number has 9 tens and 4 ones?S
What number has 2 tens and 2 ones?E
What number has 5 tens and 1 one?H
What number has 8 tens and 9 ones?I
0/14 letters found
Clue 2
Addition
You add up all the amber rocks found near the dino nest.
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
19
9
20
15
18
2
3
8
7
16
2
T
19
2
4
13
6
20
7
12
12
14
5
12
10
T
19
10
13
13
T
19
14
9
3
8
T
19
11 + 8 =T
11 + 4 =C
2 + 1 =I
10 + 8 =K
12 + 4 =U
8 + 6 =P
2 + 3 =L
6 + 4 =F
3 + 1 =H
1 + 5 =W
2 + 6 =N
8 + 5 =O
7 + 2 =R
4 + 3 =D
5 + 7 =E
9 + 11 =A
1 + 1 =S
0/17 letters found
Clue 3
Subtraction
You count how many fossil teeth are missing from the case.
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
7
5
9
18
1
9
2
14
17
4
8
1
3
16
2
1
13
16
3
6
2
11
3
15
4
10
5
8
18
T
7
11
9
13 - 6 =T
11 - 7 =D
16 - 8 =I
20 - 2 =S
12 - 9 =O
16 - 5 =L
20 - 5 =U
19 - 3 =R
19 - 2 =Y
17 - 7 =W
10 - 1 =E
3 - 2 =N
16 - 2 =K
9 - 3 =M
11 - 9 =A
6 - 1 =H
14 - 1 =F
0/17 letters found
Clue 4
Skip counting
You count the footprint trails by twos down the muddy 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.
S
30
16
120
120
10
28
8
S
30
16
39
40
28
S
30
15
28
40
8
39
S
30
120
35
26
35
28
39
26
15
28
9
16
9
28
S
30
26
Skip-count by 10s. Fill the blank: 10, 20, ___, 40, 50S
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, ___, 30, 32E
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, ___, 45, 50L
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, ___, 12, 14P
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, ___, 28, 30T
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, ___, 42, 45A
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, ___, 18, 20C
Skip-count by 2s. Fill the blank: 2, 4, 6, ___, 10, 12D
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, ___, 18, 21H
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, ___, 40, 45F
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, ___, 130, 140O
Skip-count by 3s. Fill the blank: 3, 6, ___, 12, 15R
0/12 letters found
Clue 5
Missing addends — the last clue
You figure out how many more fern leaves are needed to trap the thief.
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
9 + ___ = 16
6 + ___ = 14
4 + ___ = 9
1 + ___ = 11
9 + ___ = 20
9 + ___ = 10
1 + ___ = 13
8 + ___ = 14
6 + ___ = 10
10 + ___ = 12
7 + ___ = 16
Step 2 — cross out the sentence with each answer
1.The villain dashed like a raptor, then flew above with giant wings.
2.The villain dashed like a raptor, then walked through hot lava rock.
3.The villain bashed with armor, then used night vision in the dark.
4.The villain bashed with armor, then flew above with giant wings.
5.The villain whipped its spiked tail, then blended in with camouflage skin.
6.The villain charged like a trike, then blended in with camouflage skin.
7.The villain dashed like a raptor, then dug deep into the mud.
8.The villain charged like a trike, then flew above with giant wings.
9.The villain whipped its spiked tail, then flew above with giant wings.
10.The villain whipped its spiked tail, then used night vision in the dark.
11.The villain dashed like a raptor, then used night vision in the dark.
12.The villain roared like a rex, then used night vision in the dark.
Solve it
Name the culprit
Choose the one suspect left standing.
Answer Key — The Case of the Roaring Dino
Culprit: Dusty (Ankylosaurus Armor · Night Vision · Left Footed Prints · Feather Crest · Loud Whistle)
- Clue 1 (Place value): "THE VILLAIN DOES NOT HAVE LAVA IMMUNITY"What number has 1 ten and 4 ones? = 14 (T) · What number has 4 tens and 5 ones? = 45 (Y) · What number has 7 tens and 7 ones? = 77 (N) · What number has 7 tens and 0 ones? = 70 (M) · What number has 7 tens and 4 ones? = 74 (U) · What number has 9 tens and 3 ones? = 93 (V) · What number has 2 tens and 3 ones? = 23 (D) · What number has 3 tens and 3 ones? = 33 (L) · What number has 6 tens and 5 ones? = 65 (O) · What number has 4 tens and 2 ones? = 42 (A) · What number has 9 tens and 4 ones? = 94 (S) · What number has 2 tens and 2 ones? = 22 (E) · What number has 5 tens and 1 one? = 51 (H) · What number has 8 tens and 9 ones? = 89 (I)
- Clue 2 (Addition): "TRACKS IN DUST SHOW A DEEP LEFT FOOT PRINT"11 + 8 = 19 (T) · 11 + 4 = 15 (C) · 2 + 1 = 3 (I) · 10 + 8 = 18 (K) · 12 + 4 = 16 (U) · 8 + 6 = 14 (P) · 2 + 3 = 5 (L) · 6 + 4 = 10 (F) · 3 + 1 = 4 (H) · 1 + 5 = 6 (W) · 2 + 6 = 8 (N) · 8 + 5 = 13 (O) · 7 + 2 = 9 (R) · 4 + 3 = 7 (D) · 5 + 7 = 12 (E) · 9 + 11 = 20 (A) · 1 + 1 = 2 (S)
- Clue 3 (Subtraction): "THE SNEAKY DINO RAN FROM A LOUD WHISTLE"13 - 6 = 7 (T) · 11 - 7 = 4 (D) · 16 - 8 = 8 (I) · 20 - 2 = 18 (S) · 12 - 9 = 3 (O) · 16 - 5 = 11 (L) · 20 - 5 = 15 (U) · 19 - 3 = 16 (R) · 19 - 2 = 17 (Y) · 17 - 7 = 10 (W) · 10 - 1 = 9 (E) · 3 - 2 = 1 (N) · 16 - 2 = 14 (K) · 9 - 3 = 6 (M) · 11 - 9 = 2 (A) · 6 - 1 = 5 (H) · 14 - 1 = 13 (F)
- Clue 4 (Skip counting): "SCOOPED SCALES HELD A SOFT FEATHER CREST"Skip-count by 10s. Fill the blank: 10, 20, ___, 40, 50 = 30 (S) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, ___, 30, 32 = 28 (E) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, ___, 45, 50 = 40 (L) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, ___, 12, 14 = 10 (P) · 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 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, ___, 42, 45 = 39 (A) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, ___, 18, 20 = 16 (C) · 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, ___, 18, 21 = 15 (H) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, ___, 40, 45 = 35 (F) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, ___, 130, 140 = 120 (O) · Skip-count by 3s. Fill the blank: 3, 6, ___, 12, 15 = 9 (R)
- Clue 5 (Missing addends): surviving statement (box 3) → Dusty9 + ___ = 16 = 7 · 6 + ___ = 14 = 8 · 4 + ___ = 9 = 5 · 1 + ___ = 11 = 10 · 9 + ___ = 20 = 11 · 9 + ___ = 10 = 1 · 1 + ___ = 13 = 12 · 8 + ___ = 14 = 6 · 6 + ___ = 10 = 4 · 10 + ___ = 12 = 2 · 7 + ___ = 16 = 9
About this mystery
- Grade level
- Grade 1 math
- Math topics
- Place value, Addition, Subtraction, Skip counting, Missing addends
- Reading level
- grades 1-2
- Theme
- The Case of the Roaring Dino — set in Dino Valley Discovery Park
- Format
- Interactive online & printable worksheet with answer key
- Solution
- One unique, verified culprit among 21 suspects