🚀 Space and PlanetsGrade 7Reading: grades 5-6Place valueAdditionMultiplicationSkip countingMissing addends

The Cosmic Crystal Caper

A high-energy glowing moon crystal has vanished from the research lab on Lunar Outpost Alpha! Someone snuck past the security sensors during the orbital shift. Work through the station clues to unmask the space rogue before the supply shuttle leaves for Mars.

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	Suit Gear	Glove Dominance	Helmet Stripe	Defensive Counter balance
Peggy Whitson	Pulse Beam	Solar Shield	Right Handed	Crimson Stripe	Strobe Flare
Kalpana Chawla	Laser Torch	Solar Shield	Left Handed	Silver Stripe	Magnet Pulser
Eileen Collins	Laser Torch	Thruster Pack	Left Handed	Silver Stripe	Magnet Pulser
Chris Hadfield	Pulse Beam	Solar Shield	Right Handed	Silver Stripe	Magnet Pulser
Guion Bluford	Pulse Beam	Thruster Pack	Right Handed	Gold Stripe	Strobe Flare
Ellen Ochoa	Pulse Beam	Stealth Cloak	Left Handed	Gold Stripe	Strobe Flare
Sally Ride	Laser Torch	Cargo Net	Right Handed	Crimson Stripe	Magnet Pulser
Mark Kelly	Plasma Cutter	Cargo Net	Left Handed	Crimson Stripe	Strobe Flare
Sunita Williams	Pulse Beam	Radio Jammer	Right Handed	Crimson Stripe	Magnet Pulser
Robert Crippen	Laser Torch	Cargo Net	Left Handed	Silver Stripe	Foam Spray
Victor Glover	Gravity Hook	Cargo Net	Right Handed	Crimson Stripe	Magnet Pulser
Story Musgrave	Gravity Hook	Stealth Cloak	Right Handed	Crimson Stripe	Strobe Flare
Stephanie Wilson	Plasma Cutter	Stealth Cloak	Right Handed	Gold Stripe	Foam Spray
Mae Jemison	Laser Torch	Cargo Net	Right Handed	Crimson Stripe	Strobe Flare
Leland Melvin	Gravity Hook	Radio Jammer	Left Handed	Gold Stripe	Magnet Pulser
Buzz Aldrin	Gravity Hook	Cargo Net	Right Handed	Crimson Stripe	Foam Spray
Anousheh Ansari	Jet Booster	Thruster Pack	Right Handed	Crimson Stripe	Strobe Flare
Joan Higginbotham	Laser Torch	Thruster Pack	Right Handed	Crimson Stripe	Strobe Flare
Bernard Harris	Pulse Beam	Stealth Cloak	Right Handed	Gold Stripe	Foam Spray
Jessica Meir	Jet Booster	Thruster Pack	Right Handed	Silver Stripe	Magnet Pulser
John Glenn	Gravity Hook	Stealth Cloak	Right Handed	Silver Stripe	Strobe Flare

Clue 1

Place value

The station telemetry monitor displayed encrypted coordinate codes, highlighting specific digit positions on the screen.

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

1000

8000

9000

100

8000

800

1000

5000

500

1000

9000

8000

1000

8000

3000

1000

800

3000

500

700

What is the value of the 1 in 61,556?T

What is the value of the 1 in 778,516?A

What is the value of the 7 in 85,075?H

What is the value of the 3 in 13,476?L

What is the value of the 7 in 339,741?K

What is the value of the 8 in 65,850?C

What is the value of the 9 in 39,671?U

What is the value of the 8 in 56,384?S

What is the value of the 5 in 22,597?O

What is the value of the 8 in 698,013?E

What is the value of the 5 in 15,749?D

What is the value of the 1 in 74,144?P

What is the value of the 9 in 122,594?I

What is the value of the 4 in 97,841?N

0/14 letters found

Clue 2

Addition

A deck engineer tallied up the spare oxygen tanks stored across the three cargo bays.

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

4739

2583

6412

3263

9758

6974

6157

4739

7928

2583

9000

8756

6412

8756

6157

3263

5379

9758

5379

9000

7928

2583

6667

2069

3263

8756

6157

6412

2144

8756

2282 + 2457 =W

3308 + 6450 =E

1206 + 2057 =N

3796 + 4960 =H

1959 + 4198 =A

3662 + 5338 =G

678 + 1391 =O

3189 + 3478 =P

2853 + 2526 =D

1432 + 712 =C

3779 + 3195 =S

1469 + 1114 =I

2591 + 5337 =R

2962 + 3450 =T

0/14 letters found

Clue 3

Multiplication facts (1-12)

The solar array grid was organized into equal rows of solar panels waiting for inspection.

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

121

8 × 3 =D

6 × 11 =A

12 × 7 =I

7 × 7 =U

7 × 10 =B

1 × 2 =F

8 × 12 =T

5 × 3 =E

8 × 11 =H

11 × 7 =M

11 × 11 =N

11 × 9 =R

11 × 1 =O

6 × 2 =S

7 × 2 =L

0/15 letters found

Clue 4

Skip counting

The security lights flashed in a steady repeating pattern down the launch corridor.

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

110

120

Skip-count by 2s. Fill the blank: 2, 4, 6, ___, 10, 12S

Skip-count by 3s. Fill the blank: 3, 6, ___, 12, 15N

Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 39, ___, 45, 48P

Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, ___, 36, 39U

Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, ___, 28, 30M

Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, ___, 50, 55A

Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, ___, 130, 140K

Skip-count by 2s. Fill the blank: 2, 4, ___, 8, 10O

Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, ___, 24, 26C

Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, ___, 27, 30R

Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, ___, 18, 20E

Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, ___, 65, 70T

Skip-count by 5s. Fill the blank: 5, 10, 15, 20, ___, 30, 35L

Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, ___, 100, 110I

Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, ___, 120, 130F

0/15 letters found

Clue 5

Missing addends — the last clue

The life support log recorded total energy units used, but one section was missing from the summary.

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

24 + ___ = 36

15 + ___ = 19

28 + ___ = 35

18 + ___ = 20

13 + ___ = 24

4 + ___ = 5

16 + ___ = 24

10 + ___ = 15

5 + ___ = 11

5 + ___ = 8

28 + ___ = 38

Step 2 — cross out the sentence with each answer

1.The villain sped past the navigation deck, then trapped the robotic helper drone.

2.The villain sped past the navigation deck, then blocked the solar flare sensors.

3.The villain grabbed the heavy research container, then vanished from the radar display.

4.The villain sped past the navigation deck, then escaped into the dark asteroid belt.

5.The villain sped past the navigation deck, then vanished from the radar display.

6.The villain melted the main vault lock, then trapped the robotic helper drone.

7.The villain blasted the security grid, then blocked the solar flare sensors.

8.The villain grabbed the heavy research container, then blocked the solar flare sensors.

9.The villain sliced through the station bulkhead, then trapped the robotic helper drone.

10.The villain grabbed the heavy research container, then escaped into the dark asteroid belt.

11.The villain blasted the security grid, then escaped into the dark asteroid belt.

12.The villain sliced through the station bulkhead, then escaped into the dark asteroid belt.

Solve it

Name the culprit

Choose the one suspect left standing.

Answer Key — The Cosmic Crystal Caper

Culprit: Mae Jemison (Laser Torch · Cargo Net · Right Handed · Crimson Stripe · Strobe Flare)

Clue 1 (Place value): "THE SUSPECT DID NOT USE STEALTH CLOAK"
What is the value of the 1 in 61,556? = 1000 (T) · What is the value of the 1 in 778,516? = 10 (A) · What is the value of the 7 in 85,075? = 70 (H) · What is the value of the 3 in 13,476? = 3000 (L) · What is the value of the 7 in 339,741? = 700 (K) · What is the value of the 8 in 65,850? = 800 (C) · What is the value of the 9 in 39,671? = 9000 (U) · What is the value of the 8 in 56,384? = 80 (S) · What is the value of the 5 in 22,597? = 500 (O) · What is the value of the 8 in 698,013? = 8000 (E) · What is the value of the 5 in 15,749? = 5000 (D) · What is the value of the 1 in 74,144? = 100 (P) · What is the value of the 9 in 122,594? = 90 (I) · What is the value of the 4 in 97,841? = 40 (N)
Clue 2 (Addition): "WITNESS SAW RIGHT HANDED GRIP ON HATCH"
2282 + 2457 = 4739 (W) · 3308 + 6450 = 9758 (E) · 1206 + 2057 = 3263 (N) · 3796 + 4960 = 8756 (H) · 1959 + 4198 = 6157 (A) · 3662 + 5338 = 9000 (G) · 678 + 1391 = 2069 (O) · 3189 + 3478 = 6667 (P) · 2853 + 2526 = 5379 (D) · 1432 + 712 = 2144 (C) · 3779 + 3195 = 6974 (S) · 1469 + 1114 = 2583 (I) · 2591 + 5337 = 7928 (R) · 2962 + 3450 = 6412 (T)
Clue 3 (Multiplication facts (1-12)): "DEFENDER USED STROBE FLARE TO BLIND THEM"
8 × 3 = 24 (D) · 6 × 11 = 66 (A) · 12 × 7 = 84 (I) · 7 × 7 = 49 (U) · 7 × 10 = 70 (B) · 1 × 2 = 2 (F) · 8 × 12 = 96 (T) · 5 × 3 = 15 (E) · 8 × 11 = 88 (H) · 11 × 7 = 77 (M) · 11 × 11 = 121 (N) · 11 × 9 = 99 (R) · 11 × 1 = 11 (O) · 6 × 2 = 12 (S) · 7 × 2 = 14 (L)
Clue 4 (Skip counting): "SUIT LEFT CRIMSON STRIPE FLECKS AT SITE"
Skip-count by 2s. Fill the blank: 2, 4, 6, ___, 10, 12 = 8 (S) · Skip-count by 3s. Fill the blank: 3, 6, ___, 12, 15 = 9 (N) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 39, ___, 45, 48 = 42 (P) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, ___, 36, 39 = 33 (U) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, ___, 28, 30 = 26 (M) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, ___, 50, 55 = 45 (A) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, ___, 130, 140 = 120 (K) · Skip-count by 2s. Fill the blank: 2, 4, ___, 8, 10 = 6 (O) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, ___, 24, 26 = 22 (C) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, ___, 27, 30 = 24 (R) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, ___, 18, 20 = 16 (E) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, ___, 65, 70 = 60 (T) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, ___, 30, 35 = 25 (L) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, ___, 100, 110 = 90 (I) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, ___, 120, 130 = 110 (F)
Clue 5 (Missing addends): surviving statement (box 9) → Mae Jemison
24 + ___ = 36 = 12 · 15 + ___ = 19 = 4 · 28 + ___ = 35 = 7 · 18 + ___ = 20 = 2 · 13 + ___ = 24 = 11 · 4 + ___ = 5 = 1 · 16 + ___ = 24 = 8 · 10 + ___ = 15 = 5 · 5 + ___ = 11 = 6 · 5 + ___ = 8 = 3 · 28 + ___ = 38 = 10

About this mystery

Grade level: Grade 7 math
Math topics: Place value, Addition, Multiplication, Skip counting, Missing addends
Reading level: grades 5-6
Theme: The Cosmic Crystal Caper — set in Lunar Outpost Alpha
Format: Interactive online & printable worksheet with answer key
Solution: One unique, verified culprit among 21 suspects

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