🔎 Disney, Halloween, Pumpkins,Grade 2Reading: grades 3-4Place valueAdditionRoundingSkip countingMissing addends
Case of the Vanishing Golden Owl
Overnight, the Golden Owl vanished from its glass case at the Riverside Museum. Twenty-one people had a key to the building, and one of them is the thief. Solve each clue's math to decode it, cross suspects off the list, and name the one person left.
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 | Specialty | Gadget | Hand | Hat | Weakness |
|---|---|---|---|---|---|
| Opal Reed | Lock Picking | Grappling Hook | Right-handed | Yellow | Peanuts |
| Bram Kettle | Lock Picking | Night Goggles | Right-handed | Red | Peanuts |
| Penny Quill | Sneaking | Rubber Gloves | Left-handed | Blue | Peanuts |
| Hazel Finch | Disguises | Roller Skates | Right-handed | Yellow | Bells |
| Clem Button | Wall Climbing | Night Goggles | Left-handed | Blue | Peanuts |
| Daisy Nook | Code Cracking | Night Goggles | Left-handed | Red | Peanuts |
| Mabel Stone | Code Cracking | Glider Wings | Right-handed | Red | Bells |
| Ziggy Plum | Lock Picking | Grappling Hook | Right-handed | Red | Peanuts |
| Felix Tumble | Code Cracking | Roller Skates | Right-handed | Yellow | Bells |
| Rufus Brindle | Lock Picking | Grappling Hook | Right-handed | Red | Bells |
| Milo Tuck | Disguises | Glider Wings | Left-handed | Blue | Cats |
| Otis Crumb | Disguises | Night Goggles | Right-handed | Yellow | Peanuts |
| Hugo Flint | Disguises | Glider Wings | Right-handed | Yellow | Peanuts |
| Tilly Sprocket | Wall Climbing | Rubber Gloves | Right-handed | Yellow | Peanuts |
| Jasper Dunn | Code Cracking | Night Goggles | Left-handed | Yellow | Peanuts |
| Wren Hollis | Wall Climbing | Glider Wings | Left-handed | Red | Bells |
| Barnaby Root | Code Cracking | Glider Wings | Right-handed | Blue | Peanuts |
| Rosie Vane | Wall Climbing | Grappling Hook | Left-handed | Yellow | Bells |
| Dot Marigold | Disguises | Roller Skates | Right-handed | Yellow | Peanuts |
| Percy Wick | Disguises | Grappling Hook | Left-handed | Blue | Peanuts |
| Nell Copper | Disguises | Night Goggles | Right-handed | Red | Cats |
Clue 1
Place value
Detective, check the magic register lock! Break down the place values to open the chest and get your first 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
51
14
11
T
51
14
70
11
21
59
85
90
90
39
T
51
16
41
70
89
11
What number has 5 tens and 1 one?T
What number has 8 tens and 9 ones?D
What number has 2 tens and 1 one?F
What number has 1 ten and 1 one?E
What number has 4 tens and 1 one?L
What number has 7 tens and 0 ones?I
What number has 1 ten and 4 ones?H
What number has 5 tens and 9 ones?C
What number has 1 ten and 6 ones?G
What number has 3 tens and 9 ones?O
What number has 9 tens and 0 ones?N
What number has 8 tens and 5 ones?A
0/12 letters found
Clue 2
Addition
Count the glowing jack-o-lanterns along the path! Add up both rows to find out what happened next.
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
73
53
40
A
73
91
77
33
A
73
56
84
22
68
84
22
95
68
81
56
91
95
84
68
91
95
53
22
84
22
A
73
44
77
68
77
47 + 26 =A
36 + 17 =G
22 + 18 =U
18 + 26 =N
39 + 38 =D
58 + 37 =I
7 + 15 =H
15 + 18 =S
24 + 44 =E
24 + 57 =F
48 + 43 =R
21 + 35 =W
52 + 32 =T
0/13 letters found
Clue 3
Rounding
The spooky radar screen shows a distance rounded to the nearest ten! Round correctly to unlock a secret message.
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
900
40
700
T
900
40
20
700
70
50
60
700
700
200
700
30
60
700
80
800
80
400
80
600
90
70
300
700
80
60
500
T
900
50
Round 858 to the nearest hundredT
Round 372 to the nearest hundredB
Round 20 to the nearest tenI
Round 29 to the nearest tenD
Round 675 to the nearest hundredE
Round 93 to the nearest tenO
Round 768 to the nearest hundredR
Round 629 to the nearest hundredG
Round 326 to the nearest hundredP
Round 493 to the nearest hundredU
Round 50 to the nearest tenS
Round 67 to the nearest tenF
Round 83 to the nearest tenA
Round 173 to the nearest hundredZ
Round 44 to the nearest tenH
Round 60 to the nearest tenN
0/16 letters found
Clue 4
Skip counting
Follow the wrapper trail across the plaza! Skip count by fives to track where the villain ran.
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
90
65
50
120
120
21
60
25
A
90
80
80
25
39
50
A
90
70
60
A
90
22
55
A
90
27
20
25
80
21
24
80
25
50
55
A
90
22
50
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, ___, 100, 110A
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, ___, 90, 100T
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, ___, 30, 35H
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, ___, 70, 80W
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, ___, 30, 33U
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, ___, 27, 30N
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, ___, 130, 140L
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, ___, 70, 75Y
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, ___, 24, 26S
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, ___, 60, 70E
Skip-count by 5s. Fill the blank: 5, 10, 15, ___, 25, 30G
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, ___, 75, 80D
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, 9, 12, 15, 18, ___, 24, 27O
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, ___, 42, 45R
0/15 letters found
Clue 5
Missing addends — the last clue
The candy display jar is only half full! Find the missing number to solve the case.
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 + ___ = 8
3 + ___ = 6
4 + ___ = 14
9 + ___ = 17
10 + ___ = 11
3 + ___ = 14
3 + ___ = 10
10 + ___ = 12
6 + ___ = 12
5 + ___ = 10
7 + ___ = 19
Step 2 — cross out the sentence with each answer
1.The villain slips in dressed as a night guard, then swings down from the skylight on a grappling hook.
2.The villain picks the lock on the side door, then lifts the glass without leaving fingerprints.
3.The villain picks the lock on the side door, then swings down from the skylight on a grappling hook.
4.The villain slips in dressed as a night guard, then zooms down the hall on roller skates.
5.The villain climbs the wall to an open window, then zooms down the hall on roller skates.
6.The villain tiptoes past the sleeping guard, then finds the case in the dark with night goggles.
7.The villain cracks the alarm code, then zooms down the hall on roller skates.
8.The villain climbs the wall to an open window, then swings down from the skylight on a grappling hook.
9.The villain climbs the wall to an open window, then lifts the glass without leaving fingerprints.
10.The villain slips in dressed as a night guard, then finds the case in the dark with night goggles.
11.The villain slips in dressed as a night guard, then lifts the glass without leaving fingerprints.
12.The villain tiptoes past the sleeping guard, then lifts the glass without leaving fingerprints.
Solve it
Name the culprit
Choose the one suspect left standing.
Answer Key — Case of the Vanishing Golden Owl
Culprit: Tilly Sprocket (Wall Climbing · Rubber Gloves · Right-handed · Yellow · Peanuts)
- Clue 1 (Place value): "THE THIEF CANNOT GLIDE"What number has 5 tens and 1 one? = 51 (T) · What number has 8 tens and 9 ones? = 89 (D) · What number has 2 tens and 1 one? = 21 (F) · What number has 1 ten and 1 one? = 11 (E) · What number has 4 tens and 1 one? = 41 (L) · What number has 7 tens and 0 ones? = 70 (I) · What number has 1 ten and 4 ones? = 14 (H) · What number has 5 tens and 9 ones? = 59 (C) · What number has 1 ten and 6 ones? = 16 (G) · What number has 3 tens and 9 ones? = 39 (O) · What number has 9 tens and 0 ones? = 90 (N) · What number has 8 tens and 5 ones? = 85 (A)
- Clue 2 (Addition): "A GUARD SAW THE THIEF WRITE RIGHT HANDED"47 + 26 = 73 (A) · 36 + 17 = 53 (G) · 22 + 18 = 40 (U) · 18 + 26 = 44 (N) · 39 + 38 = 77 (D) · 58 + 37 = 95 (I) · 7 + 15 = 22 (H) · 15 + 18 = 33 (S) · 24 + 44 = 68 (E) · 24 + 57 = 81 (F) · 48 + 43 = 91 (R) · 21 + 35 = 56 (W) · 52 + 32 = 84 (T)
- Clue 3 (Rounding): "THE THIEF SNEEZED NEAR A BAG OF PEANUTS"Round 858 to the nearest hundred = 900 (T) · Round 372 to the nearest hundred = 400 (B) · Round 20 to the nearest ten = 20 (I) · Round 29 to the nearest ten = 30 (D) · Round 675 to the nearest hundred = 700 (E) · Round 93 to the nearest ten = 90 (O) · Round 768 to the nearest hundred = 800 (R) · Round 629 to the nearest hundred = 600 (G) · Round 326 to the nearest hundred = 300 (P) · Round 493 to the nearest hundred = 500 (U) · Round 50 to the nearest ten = 50 (S) · Round 67 to the nearest ten = 70 (F) · Round 83 to the nearest ten = 80 (A) · Round 173 to the nearest hundred = 200 (Z) · Round 44 to the nearest ten = 40 (H) · Round 60 to the nearest ten = 60 (N)
- Clue 4 (Skip counting): "A YELLOW HAT THREAD WAS CAUGHT ON THE CASE"Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, ___, 100, 110 = 90 (A) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, ___, 90, 100 = 80 (T) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, ___, 30, 35 = 25 (H) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, ___, 70, 80 = 60 (W) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, ___, 30, 33 = 27 (U) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, ___, 27, 30 = 24 (N) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, ___, 130, 140 = 120 (L) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, ___, 70, 75 = 65 (Y) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, ___, 24, 26 = 22 (S) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, ___, 60, 70 = 50 (E) · Skip-count by 5s. Fill the blank: 5, 10, 15, ___, 25, 30 = 20 (G) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, ___, 75, 80 = 70 (D) · 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, 9, 12, 15, 18, ___, 24, 27 = 21 (O) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, ___, 42, 45 = 39 (R)
- Clue 5 (Missing addends): surviving statement (box 9) → Tilly Sprocket4 + ___ = 8 = 4 · 3 + ___ = 6 = 3 · 4 + ___ = 14 = 10 · 9 + ___ = 17 = 8 · 10 + ___ = 11 = 1 · 3 + ___ = 14 = 11 · 3 + ___ = 10 = 7 · 10 + ___ = 12 = 2 · 6 + ___ = 12 = 6 · 5 + ___ = 10 = 5 · 7 + ___ = 19 = 12
About this mystery
- Grade level
- Grade 2 math
- Math topics
- Place value, Addition, Rounding, Skip counting, Missing addends
- Reading level
- grades 3-4
- Theme
- Case of the Vanishing Golden Owl — set in the Riverside Museum
- Format
- Interactive online & printable worksheet with answer key
- Solution
- One unique, verified culprit among 21 suspects