🐉 Dragons, fairies, witches, fGrade 5Reading: grades 5-6Place valueRoundingSkip countingAdditionDivision
The Case of the Missing Codex
The Grand Codex of Whispering Isles has vanished from the High Conservatory. Someone breached the library wards and stole the legendary spellbook before midnight.
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 | Main Magic | Secondary Magic | Dominant Hand | Hair Style | Magical Weakness |
|---|---|---|---|---|---|
| Jasper Moon | FAERIE GLOW | BEAST WHISPER | LEFT HANDED | COPPER CURLS | SUN FLOWER |
| Archmage Elara | FAERIE GLOW | FLIGHT MANTLE | RIGHT HANDED | SILVER LOCKS | SUN FLOWER |
| Gideon Grim | TALISMAN CHARM | SPELL SCRIPTS | LEFT HANDED | SILVER LOCKS | COLD IRON |
| Gwen Shadow | DRAGON FIRE | SPELL SCRIPTS | RIGHT HANDED | COPPER CURLS | COLD IRON |
| Lyra Song | DRAGON FIRE | BEAST WHISPER | RIGHT HANDED | COPPER CURLS | COLD IRON |
| Ignis Pyre | DRAGON FIRE | SPELL SCRIPTS | LEFT HANDED | EMERALD BRAIDS | MOON POWDER |
| Seraphina Frost | DRAGON FIRE | SHADOW CLOAK | RIGHT HANDED | SILVER LOCKS | MOON POWDER |
| Orion Sage | HEX WEAVING | STAR SHIELD | RIGHT HANDED | COPPER CURLS | MOON POWDER |
| Vesper Willow | FAERIE GLOW | SPELL SCRIPTS | LEFT HANDED | EMERALD BRAIDS | MOON POWDER |
| Astrid Starling | DRAGON FIRE | FLIGHT MANTLE | LEFT HANDED | EMERALD BRAIDS | COLD IRON |
| Fiona Fern | HEX WEAVING | STAR SHIELD | RIGHT HANDED | COPPER CURLS | COLD IRON |
| Sylas Thorn | DRAGON FIRE | BEAST WHISPER | LEFT HANDED | COPPER CURLS | MOON POWDER |
| Cassian Raven | DRAGON FIRE | FLIGHT MANTLE | LEFT HANDED | SILVER LOCKS | SUN FLOWER |
| Hazel Whispers | RUNE MAGIC | FLIGHT MANTLE | RIGHT HANDED | EMERALD BRAIDS | COLD IRON |
| Thorne Oak | DRAGON FIRE | BEAST WHISPER | RIGHT HANDED | EMERALD BRAIDS | MOON POWDER |
| Oberon Vale | FAERIE GLOW | FLIGHT MANTLE | RIGHT HANDED | EMERALD BRAIDS | COLD IRON |
| Zephyr Bramble | FAERIE GLOW | STAR SHIELD | RIGHT HANDED | COPPER CURLS | COLD IRON |
| Coralia Waverly | FAERIE GLOW | SPELL SCRIPTS | LEFT HANDED | COPPER CURLS | MOON POWDER |
| Lady Rowena | FAERIE GLOW | BEAST WHISPER | LEFT HANDED | COPPER CURLS | COLD IRON |
| Professor Balthazar | TALISMAN CHARM | SHADOW CLOAK | LEFT HANDED | COPPER CURLS | MOON POWDER |
| Rowan Ash | DRAGON FIRE | STAR SHIELD | RIGHT HANDED | COPPER CURLS | COLD IRON |
Clue 1
Place value
You examine the library ledger and analyze the digits in the magic catalog system to unlock the 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
40
30
300
9000
10
50
50
80
10
7000
60
1000
300
90
7000
1000
T
40
20
90
300
90
4000
300
50
50
90
2000
100
10
4000
T
40
90
What is the value of the 4 in 205,743?T
What is the value of the 9 in 76,391?S
What is the value of the 1 in 933,916?I
What is the value of the 2 in 12,888?C
What is the value of the 1 in 251,320?O
What is the value of the 7 in 407,241?N
What is the value of the 5 in 164,959?L
What is the value of the 3 in 97,371?E
What is the value of the 2 in 156,327?U
What is the value of the 8 in 657,384?A
What is the value of the 3 in 948,934?H
What is the value of the 4 in 974,350?P
What is the value of the 6 in 437,765?D
What is the value of the 9 in 89,864?V
What is the value of the 1 in 95,198?R
0/15 letters found
Clue 2
Rounding
A shimmering crystal sphere only displays rounded power levels on its glowing surface.
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
5000
900
430
1300
20
9000
900
T
5000
900
70
200
7000
430
7000
T
5000
900
20
430
230
9000
1300
70
50
50
430
7000
T
5000
900
430
110
2900
20
1100
1100
Round 4,853 to the nearest thousandT
Round 1,349 to the nearest hundredR
Round 72 to the nearest tenA
Round 49 to the nearest tenB
Round 855 to the nearest hundredH
Round 229 to the nearest hundredN
Round 427 to the nearest tenE
Round 9,394 to the nearest thousandG
Round 2,863 to the nearest hundredU
Round 1,051 to the nearest hundredL
Round 6,645 to the nearest thousandD
Round 106 to the nearest tenQ
Round 234 to the nearest tenF
Round 23 to the nearest tenI
0/14 letters found
Clue 3
Skip counting
Walking down the enchanted bookshelf aisle, you count the ancient tomes in rhythmic 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.
T
36
45
24
100
120
90
90
6
120
40
60
45
14
6
40
25
9
14
20
50
140
20
90
15
120
14
20
40
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, ___, 39, 42T
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, ___, 45, 50N
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, ___, 18, 21D
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, ___, 30, 35K
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, ___, 100, 110L
Skip-count by 5s. Fill the blank: 5, 10, 15, ___, 25, 30O
Skip-count by 3s. Fill the blank: 3, 6, ___, 12, 15F
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, ___, 50, 55H
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, ___, 110, 120V
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, ___, 65, 70S
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, ___, 16, 18R
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, ___, 130, 140I
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, ___, 60, 70M
Skip-count by 2s. Fill the blank: 2, 4, ___, 8, 10A
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, ___, 150, 160C
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, ___, 26, 28E
0/16 letters found
Clue 4
Addition
You combine the scattered potion pages left behind at the crime scene to total up the evidence.
Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.
C
5441
5338
2695
2695
5385
6601
C
5441
7864
6601
5367
7569
7402
5385
6601
5385
5791
6601
5338
2695
2695
5385
5791
5924
3679
4852
3061
5385
5924
5338
5338
8755
C
5441
5584
7569
5385
2997 + 2444 =C
3791 + 1793 =A
4137 + 3432 =S
2074 + 987 =H
1147 + 2532 =Y
1816 + 879 =P
4812 + 2590 =W
4542 + 2059 =R
3390 + 2534 =B
3466 + 5289 =K
3577 + 1808 =E
1692 + 3160 =T
2433 + 2934 =L
3597 + 2194 =D
2604 + 2734 =O
5346 + 2518 =U
0/16 letters found
Clue 5
Division facts (1-12) — the last clue
To clear the magical seal on the vault, you divide the enchanted gemstones equally into velvet pouches.
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
20 ÷ 4 = ?
144 ÷ 12 = ?
22 ÷ 2 = ?
20 ÷ 10 = ?
36 ÷ 12 = ?
20 ÷ 5 = ?
24 ÷ 3 = ?
56 ÷ 8 = ?
4 ÷ 4 = ?
10 ÷ 1 = ?
45 ÷ 5 = ?
Step 2 — cross out the sentence with each answer
1.The villain charged a glowing talisman, then vanished in the shadow cloak.
2.The villain wove a tricky hex, then read from the spell scripts.
3.The villain carved a powerful rune, then raised the star shield.
4.The villain carved a powerful rune, then vanished in the shadow cloak.
5.The villain ignited ancient dragon fire, then raised the star shield.
6.The villain ignited ancient dragon fire, then called out with beast whisper.
7.The villain wove a tricky hex, then called out with beast whisper.
8.The villain charged a glowing talisman, then read from the spell scripts.
9.The villain channeled bright faerie glow, then vanished in the shadow cloak.
10.The villain ignited ancient dragon fire, then donned the flight mantle.
11.The villain wove a tricky hex, then raised the star shield.
12.The villain channeled bright faerie glow, then raised the star shield.
Solve it
Name the culprit
Choose the one suspect left standing.
Answer Key — The Case of the Missing Codex
Culprit: Lyra Song (DRAGON FIRE · BEAST WHISPER · RIGHT HANDED · COPPER CURLS · COLD IRON)
- Clue 1 (Place value): "THE VILLAIN DOES NOT USE SPELL SCRIPTS"What is the value of the 4 in 205,743? = 40 (T) · What is the value of the 9 in 76,391? = 90 (S) · What is the value of the 1 in 933,916? = 10 (I) · What is the value of the 2 in 12,888? = 2000 (C) · What is the value of the 1 in 251,320? = 1000 (O) · What is the value of the 7 in 407,241? = 7000 (N) · What is the value of the 5 in 164,959? = 50 (L) · What is the value of the 3 in 97,371? = 300 (E) · What is the value of the 2 in 156,327? = 20 (U) · What is the value of the 8 in 657,384? = 80 (A) · What is the value of the 3 in 948,934? = 30 (H) · What is the value of the 4 in 974,350? = 4000 (P) · What is the value of the 6 in 437,765? = 60 (D) · What is the value of the 9 in 89,864? = 9000 (V) · What is the value of the 1 in 95,198? = 100 (R)
- Clue 2 (Rounding): "THE RIGHT HANDED THIEF GRABBED THE QUILL"Round 4,853 to the nearest thousand = 5000 (T) · Round 1,349 to the nearest hundred = 1300 (R) · Round 72 to the nearest ten = 70 (A) · Round 49 to the nearest ten = 50 (B) · Round 855 to the nearest hundred = 900 (H) · Round 229 to the nearest hundred = 200 (N) · Round 427 to the nearest ten = 430 (E) · Round 9,394 to the nearest thousand = 9000 (G) · Round 2,863 to the nearest hundred = 2900 (U) · Round 1,051 to the nearest hundred = 1100 (L) · Round 6,645 to the nearest thousand = 7000 (D) · Round 106 to the nearest ten = 110 (Q) · Round 234 to the nearest ten = 230 (F) · Round 23 to the nearest ten = 20 (I)
- Clue 3 (Skip counting): "THE VILLAIN SHRANK FROM COLD IRON"Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, ___, 39, 42 = 36 (T) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, ___, 45, 50 = 40 (N) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, ___, 18, 21 = 15 (D) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, ___, 30, 35 = 25 (K) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, ___, 100, 110 = 90 (L) · Skip-count by 5s. Fill the blank: 5, 10, 15, ___, 25, 30 = 20 (O) · Skip-count by 3s. Fill the blank: 3, 6, ___, 12, 15 = 9 (F) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, ___, 50, 55 = 45 (H) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, ___, 110, 120 = 100 (V) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, ___, 65, 70 = 60 (S) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, ___, 16, 18 = 14 (R) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, ___, 130, 140 = 120 (I) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, ___, 60, 70 = 50 (M) · Skip-count by 2s. Fill the blank: 2, 4, ___, 8, 10 = 6 (A) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, ___, 150, 160 = 140 (C) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, ___, 26, 28 = 24 (E)
- Clue 4 (Addition): "COPPER CURLS WERE DROPPED BY THE BOOK CASE"2997 + 2444 = 5441 (C) · 3791 + 1793 = 5584 (A) · 4137 + 3432 = 7569 (S) · 2074 + 987 = 3061 (H) · 1147 + 2532 = 3679 (Y) · 1816 + 879 = 2695 (P) · 4812 + 2590 = 7402 (W) · 4542 + 2059 = 6601 (R) · 3390 + 2534 = 5924 (B) · 3466 + 5289 = 8755 (K) · 3577 + 1808 = 5385 (E) · 1692 + 3160 = 4852 (T) · 2433 + 2934 = 5367 (L) · 3597 + 2194 = 5791 (D) · 2604 + 2734 = 5338 (O) · 5346 + 2518 = 7864 (U)
- Clue 5 (Division facts (1-12)): surviving statement (box 6) → Lyra Song20 ÷ 4 = 5 · 144 ÷ 12 = 12 · 22 ÷ 2 = 11 · 20 ÷ 10 = 2 · 36 ÷ 12 = 3 · 20 ÷ 5 = 4 · 24 ÷ 3 = 8 · 56 ÷ 8 = 7 · 4 ÷ 4 = 1 · 10 ÷ 1 = 10 · 45 ÷ 5 = 9
About this mystery
- Grade level
- Grade 5 math
- Math topics
- Place value, Rounding, Skip counting, Addition, Division
- Reading level
- grades 5-6
- Theme
- The Case of the Missing Codex — set in The High Conservatory of Magic
- Format
- Interactive online & printable worksheet with answer key
- Solution
- One unique, verified culprit among 21 suspects