ID Numbers

Choose this exercise

Purpose: Prompt low-pressure introductions through a mutual code-cracking conversation.

Use it when: Use at the beginning of a workshop, meeting, or retreat when participants do not know each other well and need an active, self-paced warm-up.

Skip it when: Skip when participants already know each other intimately or when the group lacks space to stand and mingle comfortably.

Group arrangement: Individual creation followed by rolling pairs

Timing: Source fits a 5 to 15 minute band; 15 minutes allows individual writing, three mingling rounds, and a brief group close.

Materials and tools

• One 3x5 index card or adhesive name badge per person
• One dark marker per person
• Masking tape or safety pins if using plain cards
• Digital whiteboard or chat tool for remote delivery

Before participants arrive

1. Place index cards and markers at participant seats or a central table.
2. Write an example card in advance to show the group.

Say this to open

We are going to create our own cryptic ID badges. On your card, write your first name at the top. Below your name, write three short alphanumeric codes that represent facts about your life, hobbies, or history. For example, '3C 2012 5M' could mean three cats, started this job in 2012, and ran five marathons. Choose facts you are happy to discuss. Then we will mingle and try to decode each other's badges.

How to run it

1. Write coded cards 4 minutes

   Give each person an index card and marker. Direct everyone to write their first name clearly on top. Below the name, each person writes 2 to 4 coded facts using numbers and letters. Remind people that every fact should be something they are willing to share publicly. Provide tape or pins to attach the card to clothing, or allow people to hold their card.

2. Mingle in pairs round one 3 minutes

   Ask participants to stand, find a partner they do not know well, and swap cards or look at each other's badges. Partners take turns making one or two guesses about what each code means. The author then reveals the true meaning and shares a brief detail. Ring a chime at 3 minutes.

3. Rotate and guess round two 3 minutes

   Direct participants to thank their partner and pair with someone new. Repeat the guessing and explanation process. Ring a chime at 3 minutes.

4. Rotate and guess round three 3 minutes

   Have participants find a third partner and repeat the exchange for one final round.

5. Whole-room wrap up 2 minutes

   Reconvene as a full room. Invite two or three volunteers to share an intriguing or surprising code they decoded from a partner.

Debrief questions

• Which code did you find hardest to decipher?
• What was a surprising fact or common interest you discovered through this exercise?

Finished output: A set of personalized coded badges and initial pair conversations across the room.

Remote

Ask each participant to change their screen display name or type into the chat their first name followed by their code, for example, 'Alex | 2D 10Y 4B'. Put participants into breakout rooms of two people for 3 minutes per round, running three rounds total with automatic rotation.

Hybrid

Remote and in-person participants can be paired via video-enabled laptops placed around the room, or remote participants can be grouped into their own breakout rooms while in-person participants mingle physically. Ensure remote people display their code clearly on camera or in their screen name so their partners can see it.

Access and participation choices

• Participants may hold their card rather than pin or stick it to clothing.
• Anyone may pass on guessing or decline to explain a specific code without giving a reason.
• Codes can reflect purely neutral professional or hobby facts, such as years living in a city or number of books read.

If the session gets stuck

Participants get stuck trying to invent overly complex math or cryptic codes.

Provide a standard prompt structure like: year of a key event, count of pets or siblings, and number of years doing a hobby.

An odd number of participants leaves one person without a partner during mingling rounds.

Form one group of three for that round, or have the facilitator pair with the extra person.

Terms used here

• Alphanumeric code: A short sequence combining numbers and letters used as a riddle to represent a personal fact.