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: 42ba57b5351e6d9d32791677f1fbd39ed0cec080ad1548b172e344111238b849

# Harvest

Participants compete or collaborate to take tokens from a shared replenishable pool across timed rounds. The group discovers how resource extraction rates affect pool replenishment and maximum sustainable yield.

**Time:** 15 minutes. Based on Dennis Meadows's simulation game in Play for Performance (January 2005).
**People:** 3 to 15. Single circle around a central bowl

## Choose this exercise

**Purpose:** Demonstrate the tension between individual short-term extraction and collective long-term resource renewal.
**Use it when:** Use when exploring shared resources, team competition versus collaboration, or sustainable system dynamics.
**Skip it when:** Skip when participants cannot sit together around a central table or when physical grabbing may provoke unwanted friction.

## Materials and tools

- 1 central bowl
- 150 to 200 small counters (wrapped candy, poker chips, or dried beans)
- 1 whistle, bell, or audio chime
- 1 countdown timer
- Whiteboard or flip chart with marker for debrief graph

## Before participants arrive

1. Count 50 tokens into the central bowl.
2. Keep the reserve of 100 to 150 tokens hidden or out of immediate reach.
3. Arrange chairs or standing room so all participants can reach the bowl equally.

## Say this to open

Here is a bowl with 50 tokens. In a moment I will sound the chime to start round one. You will have 5 seconds to take as many tokens from the bowl as you wish or are able to grab. When the chime sounds again, stop immediately. Your personal goal is to collect as many tokens for yourself as you can.

## How to run it

### 1. Introduce rules and goal (2 minutes)

Read the opening script. Explain replenishment: after each 5-second harvest, you will count the remaining tokens and double the remainder, capped at 50 total. If zero tokens remain, nothing regenerates. Run round 1 immediately before participants negotiate a group strategy.

### 2. Run harvest rounds (7 minutes)

Sound the chime to start each 5-second round. Sound it to stop. Count the remaining tokens aloud. Replenish by doubling the remainder, capped at 50. If 35 remain, add 15. If 20 remain, add 20. If 0 remain, add 0. Allow 20 seconds between rounds. If players ask to talk strategy, tell them to do whatever helps them maximize their tokens. Run 4 to 6 rounds. If the pool hits zero, run two rounds with an empty bowl.

### 3. Count personal totals and plot results (2 minutes)

Stop the game. Have each person count their collected tokens. On the whiteboard, draw the regeneration curve: horizontal axis shows remaining tokens (0 to 50), vertical axis shows tokens added (0 to 25), peaking at (25, 25).

### 4. Debrief system dynamics (4 minutes)

Facilitate a short discussion using the debrief questions. Take 3 to 4 comments from the circle on strategy shifts and real-world parallels.


## Debrief questions

- What happened to the shared pool between round one and the later rounds, and why?
- What individual temptation conflicted with the group's maximum total yield?
- Where do you see this replenishment dynamic in your daily work or common resources?

**Finished output:** A drawn regeneration curve and an agreed list of operational parallels to shared resources.

## Remote

Run in an online meeting using an interactive whiteboard or spreadsheet. Place 50 digital tokens in a shared workspace. Give players 10 seconds per round to move tokens into their private labeled boxes. Facilitator counts the remainder and adds duplicate tokens up to the 50-token cap.

## Hybrid

To avoid unfair physical advantage, form hybrid pairs where an in-person person manipulates tokens on behalf of themselves and a remote partner, or run the game purely on a shared digital board with all participants logging in via their own devices.

## Access and participation choices

- Offer an option to name an extraction number on scratch paper or point rather than physically grabbing if fine motor reach is difficult.
- Allow participants to observe, act as counter, or record round tallies without taking tokens.

## If the session gets stuck

**Aggressive reaching leads to spilled bowls or physical collision.**

Use a shallow wide tray instead of a deep bowl, or institute a one-hand rule where players pick tokens rather than snatching handfuls.

**The group depletes the bowl to zero in round one.**

Run two more 5-second rounds with an empty bowl as designed. Let the silence stand, then move directly to debriefing why immediate self-interest emptied the resource.


## Terms used here

- Maximum Sustainable Yield: The largest harvest rate that can be taken repeatedly without depleting the original stock over time.

## Sources and adaptation

Observed in Play for Performance (January 2005), published by The Thiagi Group, featuring the simulation game Harvest attributed to Dennis Meadows.

Retained Dennis Meadows's core game mechanics, 50-token pool, 5-second round timing, and replenishment formula from the January 2005 Play for Performance newsletter. Replaced the generic newsletter container title with the specific game title Harvest. Formatted standard time bands and structured facilitation steps for standard workshop delivery. Shortened step wording to stay under word limits.

[thiagi.net](https://thiagi.net/archive/www/pfp/IE4H/january2005.html)

Current run sheet: https://unitedwetransform.com/exercises/pfp-january-2005/