🚀 SpaceGrade 3Reading: grades 1-2AdditionSubtractionMultiplicationRoundingDivision

The Cosmic Crystal Caper

A sneaky space thief has stolen the glowing Power Crystal from the Cosmos Station! The Star Patrol needs your help to find the thief before they zoom away into deep space.

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	Space Tool	Special Gear	Scanner Hand	Hair Color	Weakness
Sally	rocket boots	stealth cloak	right-handed scanner	glow green hair	giant magnets
Yuri	laser blaster	stealth cloak	left-handed scanner	bright blue hair	giant magnets
Ellen	force field	metal claw	right-handed scanner	neon pink hair	giant magnets
Collins	rocket boots	radar visor	right-handed scanner	neon pink hair	giant magnets
Winston	force field	teleport pad	left-handed scanner	bright blue hair	giant magnets
Jessica	force field	stealth cloak	right-handed scanner	glow green hair	giant magnets
Mae	rocket boots	radar visor	left-handed scanner	bright blue hair	giant magnets
Chris	force field	metal claw	left-handed scanner	neon pink hair	strobe lights
James	shrink ray	teleport pad	left-handed scanner	glow green hair	strobe lights
Valentina	rocket boots	metal claw	right-handed scanner	bright blue hair	strobe lights
Charles	laser blaster	radar visor	right-handed scanner	glow green hair	sticky space foam
Buzz	rocket boots	jet pack	right-handed scanner	glow green hair	giant magnets
Victor	laser blaster	metal claw	right-handed scanner	bright blue hair	strobe lights
Neil	laser blaster	metal claw	right-handed scanner	bright blue hair	sticky space foam
John	rocket boots	radar visor	left-handed scanner	neon pink hair	giant magnets
Peggy	laser blaster	teleport pad	left-handed scanner	neon pink hair	giant magnets
Alan	gravity glove	stealth cloak	left-handed scanner	glow green hair	giant magnets
Sunita	gravity glove	radar visor	left-handed scanner	bright blue hair	strobe lights
Guy	laser blaster	metal claw	right-handed scanner	bright blue hair	giant magnets
Christina	shrink ray	metal claw	right-handed scanner	glow green hair	giant magnets
Michael	laser blaster	teleport pad	right-handed scanner	glow green hair	giant magnets

Clue 1

Addition

Cadet Leo counts the glowing space boots. He adds two piles of boots together to find the sum. This gives us our 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.

742

450

851

370

536

219

355

536

215

860

445

851

383

215

445

742

797

383

851

355

833

851

742

613

355

267

301

509 + 233 =T

367 + 493 =D

294 + 242 =I

144 + 71 =N

120 + 147 =C

517 + 334 =E

163 + 138 =K

154 + 65 =L

299 + 146 =O

275 + 522 =U

248 + 107 =A

217 + 396 =P

193 + 177 =V

483 + 350 =J

171 + 279 =H

149 + 234 =S

0/16 letters found

Clue 2

Subtraction

There are fewer fuel tanks now. Cadet Leo subtracts the stolen tanks from the start total. The left-over number shows us where to look.

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

894

221

499

703

835

490

837

188

648

458

493

576

493

673

490

837

221

837

499

648

490

458

221

188

644

188

648

490

576

851

1034 - 140 =W

256 - 68 =R

801 - 308 =H

1039 - 366 =A

729 - 271 =G

579 - 358 =E

601 - 102 =F

664 - 16 =I

944 - 241 =O

1107 - 270 =D

692 - 202 =N

904 - 328 =T

712 - 68 =P

891 - 56 =U

900 - 49 =S

0/15 letters found

Clue 3

Multiplication facts (1-12)

The cargo deck has crates in neat rows. Cadet Leo multiplies the rows by the columns. This math shows us which screen to open.

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

132

144

121

120

5 × 5 =T

11 × 3 =A

9 × 5 =W

12 × 12 =I

2 × 7 =M

9 × 6 =O

2 × 3 =G

10 × 3 =N

8 × 10 =S

1 × 1 =F

7 × 4 =D

9 × 9 =Y

11 × 11 =P

12 × 11 =H

8 × 12 =E

12 × 10 =B

0/16 letters found

Clue 4

Rounding

The radar screen only shows rounded numbers. Cadet Leo rounds the distance to the nearest ten. This gives us a secret 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.

700

9000

4000

6000

8000

200

800

6000

700

500

9000

200

300

7000

500

6000

200

5000

9000

300

7000

500

Round 671 to the nearest hundredW

Round 8,335 to the nearest thousandU

Round 8,979 to the nearest thousandE

Round 5,675 to the nearest thousandO

Round 26 to the nearest tenC

Round 37 to the nearest tenG

Round 763 to the nearest hundredD

Round 5,379 to the nearest thousandT

Round 241 to the nearest hundredN

Round 508 to the nearest hundredR

Round 252 to the nearest hundredA

Round 93 to the nearest tenL

Round 6,912 to the nearest thousandI

Round 3,897 to the nearest thousandF

Round 49 to the nearest tenH

0/15 letters found

Clue 5

Division facts (1-12) — the last clue

We have to share the moon rocks. Cadet Leo divides the rocks equally into space packs. The group size reveals the last clue.

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

6 ÷ 3 = ?

42 ÷ 6 = ?

2 ÷ 2 = ?

45 ÷ 9 = ?

110 ÷ 11 = ?

88 ÷ 8 = ?

48 ÷ 12 = ?

72 ÷ 9 = ?

24 ÷ 8 = ?

36 ÷ 3 = ?

72 ÷ 8 = ?

Step 2 — cross out the sentence with each answer

1.The villain zooms past with rocket boots, then fades into the dark with a stealth cloak.

2.The villain blocks the alarm with a force field, then fades into the dark with a stealth cloak.

3.The villain lifts the safe with a gravity glove, then checks the halls with a radar visor.

4.The villain zooms past with rocket boots, then grabs the loot with a metal claw.

5.The villain blasts a lock with a laser blaster, then grabs the loot with a metal claw.

6.The villain blasts a lock with a laser blaster, then zaps away using a teleport pad.

7.The villain shrinks the vault door with a shrink ray, then grabs the loot with a metal claw.

8.The villain lifts the safe with a gravity glove, then zaps away using a teleport pad.

9.The villain blasts a lock with a laser blaster, then checks the halls with a radar visor.

10.The villain shrinks the vault door with a shrink ray, then zaps away using a teleport pad.

11.The villain blasts a lock with a laser blaster, then fades into the dark with a stealth cloak.

12.The villain zooms past with rocket boots, then flies up high using a jet pack.

Solve it

Name the culprit

Choose the one suspect left standing.

Answer Key — The Cosmic Crystal Caper

Culprit: Michael (laser blaster · teleport pad · right-handed scanner · glow green hair · giant magnets)

Clue 1 (Addition): "THE VILLAIN DOES NOT USE A JET PACK"
509 + 233 = 742 (T) · 367 + 493 = 860 (D) · 294 + 242 = 536 (I) · 144 + 71 = 215 (N) · 120 + 147 = 267 (C) · 517 + 334 = 851 (E) · 163 + 138 = 301 (K) · 154 + 65 = 219 (L) · 299 + 146 = 445 (O) · 275 + 522 = 797 (U) · 248 + 107 = 355 (A) · 217 + 396 = 613 (P) · 193 + 177 = 370 (V) · 483 + 350 = 833 (J) · 171 + 279 = 450 (H) · 149 + 234 = 383 (S)
Clue 2 (Subtraction): "WE FOUND RIGHT HANDED FINGERPRINTS"
1034 - 140 = 894 (W) · 256 - 68 = 188 (R) · 801 - 308 = 493 (H) · 1039 - 366 = 673 (A) · 729 - 271 = 458 (G) · 579 - 358 = 221 (E) · 601 - 102 = 499 (F) · 664 - 16 = 648 (I) · 944 - 241 = 703 (O) · 1107 - 270 = 837 (D) · 692 - 202 = 490 (N) · 904 - 328 = 576 (T) · 712 - 68 = 644 (P) · 891 - 56 = 835 (U) · 900 - 49 = 851 (S)
Clue 3 (Multiplication facts (1-12)): "THE THIEF WAS STOPPED BY MAGNETS"
5 × 5 = 25 (T) · 11 × 3 = 33 (A) · 9 × 5 = 45 (W) · 12 × 12 = 144 (I) · 2 × 7 = 14 (M) · 9 × 6 = 54 (O) · 2 × 3 = 6 (G) · 10 × 3 = 30 (N) · 8 × 10 = 80 (S) · 1 × 1 = 1 (F) · 7 × 4 = 28 (D) · 9 × 9 = 81 (Y) · 11 × 11 = 121 (P) · 12 × 11 = 132 (H) · 8 × 12 = 96 (E) · 12 × 10 = 120 (B)
Clue 4 (Rounding): "WE FOUND GLOW GREEN HAIR ON THE CHAIR"
Round 671 to the nearest hundred = 700 (W) · Round 8,335 to the nearest thousand = 8000 (U) · Round 8,979 to the nearest thousand = 9000 (E) · Round 5,675 to the nearest thousand = 6000 (O) · Round 26 to the nearest ten = 30 (C) · Round 37 to the nearest ten = 40 (G) · Round 763 to the nearest hundred = 800 (D) · Round 5,379 to the nearest thousand = 5000 (T) · Round 241 to the nearest hundred = 200 (N) · Round 508 to the nearest hundred = 500 (R) · Round 252 to the nearest hundred = 300 (A) · Round 93 to the nearest ten = 90 (L) · Round 6,912 to the nearest thousand = 7000 (I) · Round 3,897 to the nearest thousand = 4000 (F) · Round 49 to the nearest ten = 50 (H)
Clue 5 (Division facts (1-12)): surviving statement (box 6) → Michael
6 ÷ 3 = 2 · 42 ÷ 6 = 7 · 2 ÷ 2 = 1 · 45 ÷ 9 = 5 · 110 ÷ 11 = 10 · 88 ÷ 8 = 11 · 48 ÷ 12 = 4 · 72 ÷ 9 = 8 · 24 ÷ 8 = 3 · 36 ÷ 3 = 12 · 72 ÷ 8 = 9

About this mystery

Grade level: Grade 3 math
Math topics: Addition, Subtraction, Multiplication, Rounding, Division
Reading level: grades 1-2
Theme: The Cosmic Crystal Caper — set in Cosmos Station
Format: Interactive online & printable worksheet with answer key
Solution: One unique, verified culprit among 21 suspects

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