🔎 ZombiesGrade 3Reading: grades 3-4Place valueAdditionSubtractionRoundingMissing addends

The Great Green Gelatin Mystery

The school cafeteria was locked tight, but someone still sneaked in and ate all the glowing green gelatin! The hungry culprit left a trail of muddy slime across the floor. You must help the detective squad track down the greedy zombie who did it.

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	Scary Power	Secret Trick	Cafeteria Clue	Costume Hair	Funny Weakness
Rick Grimes	Laser Stare	Stinky Aura	Right-handed grab	Spiky green wig	Loud music
Zoey	Mega Jump	Stinky Aura	Right-handed grab	Spiky green wig	Bubble baths
Leon Kennedy	Acid Spit	Glow Teeth	Left-handed grab	Muddy blue wig	Squeaky toys
Grave Digger Dan	Laser Stare	Stinky Aura	Left-handed grab	Muddy blue wig	Squeaky toys
Michonne	Mega Jump	Glow Teeth	Right-handed grab	Spiky green wig	Loud music
Rotty Rita	Laser Stare	Glow Teeth	Left-handed grab	Spiky green wig	Loud music
Zeke	Mega Jump	Sonic Groan	Right-handed grab	Spiky green wig	Squeaky toys
Specter Sam	Ice Breath	Glow Teeth	Right-handed grab	Spiky green wig	Squeaky toys
Ghoulish Gabe	Acid Spit	Wall Climb	Right-handed grab	Muddy blue wig	Squeaky toys
Ed	Ice Breath	Stinky Aura	Right-handed grab	Muddy blue wig	Squeaky toys
Shaun	Ice Breath	Wall Climb	Left-handed grab	Muddy blue wig	Squeaky toys
Howling Helen	Laser Stare	Wall Climb	Left-handed grab	Muddy blue wig	Squeaky toys
Bony Ben	Mega Jump	Wall Climb	Right-handed grab	Muddy blue wig	Loud music
Wanda Walker	Ice Breath	Sonic Groan	Right-handed grab	Spiky green wig	Loud music
Chris Redfield	Ice Breath	Stinky Aura	Left-handed grab	Rusty orange wig	Squeaky toys
Slobbering Steve	Ice Breath	Speed Crawl	Right-handed grab	Spiky green wig	Loud music
Jill Valentine	Mega Jump	Glow Teeth	Right-handed grab	Spiky green wig	Squeaky toys
Zack Zombie	Mega Jump	Glow Teeth	Right-handed grab	Rusty orange wig	Bubble baths
Claire Redfield	Ice Breath	Wall Climb	Right-handed grab	Spiky green wig	Loud music
Mummy Mia	Super Squeeze	Speed Crawl	Right-handed grab	Muddy blue wig	Loud music
Benny Brains	Ice Breath	Wall Climb	Left-handed grab	Spiky green wig	Loud music

Clue 1

Place value

We found a locked security box. The digital keypad shows values for hundreds, tens, and ones. Solve this place value puzzle to open the box and read the first file.

Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.

200

7000

2000

8000

300

4000

200

3000

6000

2000

400

6000

200

400

300

2000

3000

8000

9000

1000

What is the value of the 2 in 3,216?T

What is the value of the 9 in 19,150?A

What is the value of the 8 in 48,334?C

What is the value of the 2 in 92,514?E

What is the value of the 6 in 468?R

What is the value of the 6 in 6,248?O

What is the value of the 3 in 2,378?P

What is the value of the 3 in 93,109?D

What is the value of the 1 in 616?N

What is the value of the 7 in 17,093?H

What is the value of the 1 in 81,862?W

What is the value of the 2 in 3,128?U

What is the value of the 4 in 4,723?I

What is the value of the 9 in 4,195?L

What is the value of the 4 in 2,430?S

0/15 letters found

Clue 2

Addition

Muddy footprints lead down the dark hallway. We need to tally up the tracks on the left side and the right side. Add them together to get the total.

Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.

290

401

502

586

828

758

977

404

562

404

249

824

396

401

290

401

404

925

307

502

307

396

249

404

395

188 + 102 =T

620 + 357 =S

133 + 262 =B

514 + 314 =O

215 + 181 =G

167 + 140 =D

415 + 409 =I

184 + 217 =H

453 + 305 =K

337 + 225 =W

310 + 276 =C

176 + 228 =A

458 + 467 =N

175 + 327 =E

110 + 139 =R

0/15 letters found

Clue 3

Subtraction

The thief raided the snack bin. Let us count the total snack cakes we had and subtract the cakes that are now missing to see what remains.

Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.

240

746

536

172

632

338

581

536

691

536

750

187

240

557

338

201

750

822

201

313

588

632

594 - 354 =T

742 - 185 =L

333 - 146 =A

794 - 258 =E

928 - 296 =C

969 - 381 =I

436 - 123 =S

234 - 62 =Y

990 - 299 =R

520 - 319 =U

746 - 165 =W

883 - 133 =D

867 - 45 =M

1026 - 280 =H

400 - 62 =O

0/15 letters found

Clue 4

Rounding

A motion detector screen is fuzzy. It only displays zombie power numbers rounded to the nearest ten. Round the number to read the screen clearly.

Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.

6000

400

700

300

200

2000

3000

900

5000

4000

9000

300

6000

3000

4000

Round 5,513 to the nearest thousandW

Round 9,461 to the nearest thousandR

Round 86 to the nearest tenP

Round 323 to the nearest hundredN

Round 740 to the nearest hundredU

Round 73 to the nearest tenE

Round 63 to the nearest tenF

Round 182 to the nearest hundredD

Round 83 to the nearest tenA

Round 861 to the nearest hundredK

Round 3,525 to the nearest thousandG

Round 4,657 to the nearest thousandY

Round 417 to the nearest hundredO

Round 3,404 to the nearest thousandI

Round 2,052 to the nearest thousandS

0/15 letters found

Clue 5

Missing addends — the last clue

We need a target number of flashlights to search the dark gym. We have some already. Figure out how many more we must find to reach our goal.

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

5 + ___ = 13

3 + ___ = 15

3 + ___ = 13

5 + ___ = 10

5 + ___ = 14

3 + ___ = 9

2 + ___ = 9

7 + ___ = 8

9 + ___ = 20

5 + ___ = 7

5 + ___ = 9

Step 2 — cross out the sentence with each answer

1.The villain crushes the gelatin mold with a super squeeze, then zooms away on the ground using speed crawl.

2.The villain dissolves the lock with acid spit, then zooms away on the ground using speed crawl.

3.The villain leaps over the cafeteria counter, then lights up the dark room with glowing teeth.

4.The villain melts the freezer door with a laser stare, then zooms away on the ground using speed crawl.

5.The villain leaps over the cafeteria counter, then zooms away on the ground using speed crawl.

6.The villain leaps over the cafeteria counter, then shatters the kitchen windows with a sonic groan.

7.The villain crushes the gelatin mold with a super squeeze, then shatters the kitchen windows with a sonic groan.

8.The villain melts the freezer door with a laser stare, then leaves behind a terrible stinky aura.

9.The villain melts the freezer door with a laser stare, then lights up the dark room with glowing teeth.

10.The villain freezes the kitchen floor with ice breath, then shatters the kitchen windows with a sonic groan.

11.The villain dissolves the lock with acid spit, then escapes by climbing straight up the wall.

12.The villain freezes the kitchen floor with ice breath, then escapes by climbing straight up the wall.

Solve it

Name the culprit

Choose the one suspect left standing.

Answer Key — The Great Green Gelatin Mystery

Culprit: Michonne (Mega Jump · Glow Teeth · Right-handed grab · Spiky green wig · Loud music)

Clue 1 (Place value): "THE CULPRIT DOES NOT SPEED CRAWL"
What is the value of the 2 in 3,216? = 200 (T) · What is the value of the 9 in 19,150? = 9000 (A) · What is the value of the 8 in 48,334? = 8000 (C) · What is the value of the 2 in 92,514? = 2000 (E) · What is the value of the 6 in 468? = 60 (R) · What is the value of the 6 in 6,248? = 6000 (O) · What is the value of the 3 in 2,378? = 300 (P) · What is the value of the 3 in 93,109? = 3000 (D) · What is the value of the 1 in 616? = 10 (N) · What is the value of the 7 in 17,093? = 7000 (H) · What is the value of the 1 in 81,862? = 1000 (W) · What is the value of the 2 in 3,128? = 20 (U) · What is the value of the 4 in 4,723? = 4000 (I) · What is the value of the 9 in 4,195? = 90 (L) · What is the value of the 4 in 2,430? = 400 (S)
Clue 2 (Addition): "THE COOK SAW A RIGHT HANDED GRAB"
188 + 102 = 290 (T) · 620 + 357 = 977 (S) · 133 + 262 = 395 (B) · 514 + 314 = 828 (O) · 215 + 181 = 396 (G) · 167 + 140 = 307 (D) · 415 + 409 = 824 (I) · 184 + 217 = 401 (H) · 453 + 305 = 758 (K) · 337 + 225 = 562 (W) · 310 + 276 = 586 (C) · 176 + 228 = 404 (A) · 458 + 467 = 925 (N) · 175 + 327 = 502 (E) · 110 + 139 = 249 (R)
Clue 3 (Subtraction): "THEY COWERED AT LOUD MUSIC"
594 - 354 = 240 (T) · 742 - 185 = 557 (L) · 333 - 146 = 187 (A) · 794 - 258 = 536 (E) · 928 - 296 = 632 (C) · 969 - 381 = 588 (I) · 436 - 123 = 313 (S) · 234 - 62 = 172 (Y) · 990 - 299 = 691 (R) · 520 - 319 = 201 (U) · 746 - 165 = 581 (W) · 883 - 133 = 750 (D) · 867 - 45 = 822 (M) · 1026 - 280 = 746 (H) · 400 - 62 = 338 (O)
Clue 4 (Rounding): "WE FOUND A SPIKY GREEN WIG"
Round 5,513 to the nearest thousand = 6000 (W) · Round 9,461 to the nearest thousand = 9000 (R) · Round 86 to the nearest ten = 90 (P) · Round 323 to the nearest hundred = 300 (N) · Round 740 to the nearest hundred = 700 (U) · Round 73 to the nearest ten = 70 (E) · Round 63 to the nearest ten = 60 (F) · Round 182 to the nearest hundred = 200 (D) · Round 83 to the nearest ten = 80 (A) · Round 861 to the nearest hundred = 900 (K) · Round 3,525 to the nearest thousand = 4000 (G) · Round 4,657 to the nearest thousand = 5000 (Y) · Round 417 to the nearest hundred = 400 (O) · Round 3,404 to the nearest thousand = 3000 (I) · Round 2,052 to the nearest thousand = 2000 (S)
Clue 5 (Missing addends): surviving statement (box 3) → Michonne
5 + ___ = 13 = 8 · 3 + ___ = 15 = 12 · 3 + ___ = 13 = 10 · 5 + ___ = 10 = 5 · 5 + ___ = 14 = 9 · 3 + ___ = 9 = 6 · 2 + ___ = 9 = 7 · 7 + ___ = 8 = 1 · 9 + ___ = 20 = 11 · 5 + ___ = 7 = 2 · 5 + ___ = 9 = 4

About this mystery

Grade level: Grade 3 math
Math topics: Place value, Addition, Subtraction, Rounding, Missing addends
Reading level: grades 3-4
Theme: The Great Green Gelatin Mystery — set in Brainy Acres Middle School
Format: Interactive online & printable worksheet with answer key
Solution: One unique, verified culprit among 21 suspects

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