Works with Claude, ChatGPT, Gemini, or your own local model: paste this prompt and your AI will co-facilitate this exercise with you.

Help me prepare and run the exercise below. First ask for my participant count, time, setting, access needs and intended result. Check these against the stated limits. Use the supplied rules and materials. Explain any proposed changes before using them, and label them as adaptations. Do not invent source claims or require personal disclosure. Give me one step at a time when I say start. I manage the people, physical activity and clock; do not claim to observe the room. Ask me what happened before choosing a next step.

Reference revision: 4899f5d4e28663f41c0e09d1fa8f5f46e13c1e015a4cab0e57ea1867d033a0be

# Longest Shadow

Teams position their bodies outdoors in direct sunlight to cast the longest continuous unbroken shadow from a shared baseline. Groups experiment with postures and overlap, recording their longest valid measurement.

**Time:** 15 minutes. Playmeo notes up to 10 minutes of attempts. UWT sets 15 minutes to include briefing, experimentation, official measurement, and debrief.
**People:** 4 to 24. Parallel teams of 4 to 6. If numbers do not divide cleanly, form groups of 3 to 7, or assign extra participants as measuring assistants and spotters.

## Choose this exercise

**Purpose:** Coordinate physical positioning under shared environmental constraints to reach a measurable group outcome.
**Use it when:** Use outdoors on a clear, sunny day when a group needs an active physical problem-solving challenge with simple rules.
**Skip it when:** Skip on overcast or rainy days, in shaded areas, or when outdoor mobility on uneven ground is impractical.

## Materials and tools

- 1 roll of painter tape, chalk, or ground rope to mark the starting baseline
- 1 long measuring tape (at least 30 meters / 100 feet) or measuring wheel
- 1 clipboard and pencil for recording measurements

## Before participants arrive

1. Find an open, flat outdoor area with direct sunlight and no shadows from trees or buildings.
2. Mark a straight starting line with chalk, rope, or tape, aligned so shadows point away from the line.
3. Assign baseline sections with at least 3 meters of sideways clearance between teams so shadows do not overlap.

## Say this to open

Welcome outside. Your task is to work as a team to cast the longest unbroken shadow possible from your baseline mark. Your team's shadow must begin on the baseline and stretch out as one continuous dark shape with no daylight showing between bodies. You may only use your own bodies. Do not use jackets, sticks, bags, or other items. You have 4 minutes to test ideas, followed by 6 minutes for official measurements.

## How to run it

### 1. Brief rules and assign baselines (2 minutes)

Form teams of 4 to 6. Place each team at an assigned station along the baseline. Explain the two core rules: shadows must be one continuous unbroken shape starting on the baseline, and only human bodies may cast them. Show an example of an invalid broken shadow where sunlight breaks the silhouette between two members.

### 2. Experiment with arrangements (4 minutes)

Start the 4-minute practice clock. Teams test positions, postures, and connection points. Participants may stand, crouch, reach, or lie on the ground if comfortable. Remind groups that physical contact is unnecessary; only their shadows need to overlap on the ground.

### 3. Measure official shadow attempts (6 minutes)

Facilitator and designated spotters walk down the baseline measuring each team's formation. Measure in a straight line from the team baseline to the furthest unbroken point of their shadow silhouette. Record the distance on the clipboard and announce it. Each team gets one official recorded attempt, plus a second attempt if time permits.

### 4. Debrief results (3 minutes)

Gather all teams at the baseline. Announce the final recorded distances. Ask the debrief questions to the room, taking two or three brief observations from volunteers.


## Debrief questions

- What adjustments created the biggest increase in your team's shadow length?
- How did you balance stretching out farther against the risk of breaking the shadow connection?

**Finished output:** A recorded maximum shadow length measurement for each team from the shared baseline.

## Remote

This activity requires outdoor sunlight and cast shadows, so it cannot run online as the same exercise. A labeled remote alternative is Digital Silhouette Chain: on a shared digital whiteboard, each team receives an identical set of stick figures and has 5 minutes to connect them head-to-toe across a grid to cover the maximum pixel distance without breaking connections.

## Hybrid

Hybrid delivery is not recommended because remote participants cannot cast physical shadows on the shared lawn. If necessary, remote participants join by mobile video call to serve as strategic spotters, watching their team's live shadow from above to call out breaks in sunlight and direct foot positioning.

## Access and participation choices

- Participants may stand, sit in chairs, use mobility aids, or recline on grass; any posture that casts an unbroken shadow is valid.
- Physical contact is optional; shadows only need to overlap on the ground without people touching.
- Anyone who prefers not to move physically may act as a line spotter, timer, or measurement assistant.

## If the session gets stuck

**Midday sun casts very short shadows for everyone.**

Remind teams that the angle affects all groups equally. Encourage wide horizontal postures and outstretched limbs to maximize ground reach.

**A participant holds out a jacket or branch to lengthen the tip.**

Reiterate the rule that only bodies cast the shadow. Worn clothing is allowed, but detached or extended props are not.


## Terms used here

- Continuous shadow: A cast silhouette where dark shapes overlap on the ground with no visible sunlight breaking the connection.

## Sources and adaptation

Observed in Playmeo library, where it is attributed to Mark Collard.

Retained core rules from Playmeo (outdoor sunny space, common starting line, continuous unbroken shadow rule, bodies only, multiple attempts). UWT structured the 15-minute run sheet, balanced step timings with an expanded 6-minute measurement window, resolved uneven team counts with spotter roles, and added non-contact access options.

[Playmeo](https://www.playmeo.com/activities/team-building-problem-solving-activities/longest-shadow)

[Playmeo](https://www.playmeo.com/activities/team-building-problem-solving-activities/longest-shadow/)

Current run sheet: https://unitedwetransform.com/exercises/fun-outdoor-team-challenge-for-creative-thinking-longest-shadow/