Minute Mystery: The Two Glasses

Name and Purpose

• Minute Mystery: The Two Glasses is a lateral-thinking puzzle that rewards careful, logical questioning.
• Players discover how two identical situations can have different outcomes , a great entry point for thinking about cause and effect.

a.k.a.

• (No alternate names added , standalone puzzle)

Age / Group / Time / Space

• Ages 10-16 | 4-25 players | 10-15 minutes | Any seated setting , indoors, outdoors, on a bus, around a campfire
• Note: best for ages 10 and up given the complexity of the logic

Materials

• No materials needed
• Optional: a printed clue card for the facilitator

Quick-Run Card

1. Facilitator reads the clue: “Two people are each given the same drink. Both drinks are identical. One person gets very sick after drinking theirs; the other feels fine. Why?”
2. Players ask yes-or-no questions to figure out what happened.
3. Facilitator answers only yes, no, or “doesn’t matter.”
4. Players may confer quietly before asking.
5. Round ends when the group solves it or time is called , then reveal the answer.

Setup and Boundaries

• Seat players in a circle or semicircle so everyone can hear
• Signal: one raised hand = pause; two claps = time called
• No physical setup required

How to Play

1. The facilitator reads the clue: “Two people are each given the same cold drink. Both drinks are identical. One person gets very sick after drinking theirs; the other feels fine. Why?”
2. Players take turns asking yes-or-no questions. The facilitator may answer: yes, no, or “that doesn’t matter.”
3. Players can confer quietly between questions.
4. Nudge players to think about: Were the drinks really identical? What was in the ice? How quickly did each person drink?
5. If the group is stuck, offer one nudge per minute.
6. When someone arrives at the answer, the facilitator confirms. Celebrate together.

Answer (for facilitator only)

• Something harmful was in the ice cubes of both drinks. One person drank quickly, finishing before the ice melted. The other person sipped slowly, and the ice melted into the drink. The mystery turns on how quickly each person drank.
• Note: the original puzzle used the word ‘poison’ and framed this as a fatal outcome. For this version, the facilitator may describe the effect as ‘getting very sick’ rather than a fatal outcome. The logical core of the puzzle remains unchanged.

I-OPt Options

• Start , A (Active): Ask the first question and lead the inquiry
• Start , S (Support): Listen carefully and build on others’ thinking
• Start , Q (Quiet): Sit with the clue and think before asking anything
• Start , O (Observer): Watch the group’s approach for a round before joining
• Mid , A (Active): Try a new line of questioning if the group gets stuck
• Mid , S (Support): Summarise confirmed answers to organise group thinking
• Mid , Q (Quiet): Ask one well-timed question when ready
• Mid , O (Observer): Join when a question comes to you
• Late , A (Active): Make the final deductive leap and name the answer
• Late , S (Support): Help the group connect the last clues
• End , A (Active): Walk through the logical chain
• End , S (Support): Celebrate the group’s reasoning
• End , O (Observer): Share which question was the turning point

Inclusion Adaptations

• Players who prefer not to speak aloud can pass written questions to a partner
• Small groups of 2-3 may confer and ask as a team

Stewardship Moment

• No materials, no footprint
• Optional connection: “This puzzle is about paying attention to small details. What small details at camp do we need to notice to keep our space safe and welcoming?”

Consent

• Pre-brief: “This puzzle has a surprising twist , and there are no wrong questions. Ask whatever comes to mind.”
• Mid-game check: After 5 minutes, pause. “Still with us? Thumbs up, sideways, or down.”
• Opt-out/re-entry: Listen quietly at any time and jump in when ready.

Risks and Mitigation

• Older players may find the puzzle straightforward: challenge them to solve it in five questions or fewer
• The concept of something harmful in food or drink may be unsettling for some players: facilitators may frame it as a science-style puzzle (“something in the ice changed when it melted”) without dwelling on the outcome
• One player guesses immediately: ask them to hold their answer so others can reason through it

Warm-Up Suggestions

• “True or False”: facilitator makes three statements; group decides which is false
• “Same or Different?”: facilitator describes two situations; group decides what the key difference is

Debrief Questions

• What? “What was the key detail that cracked the puzzle?”
• So What? “What assumptions did you make at the start? How did you change them?”
• Now What? “When is it important to slow down and look for the small detail you might have missed?”

Cleanup and Reset

• No materials to reset
• Move to the next mystery or activity