In one line: A deceptively simple online game in which running a lemonade stand for thirty days teaches pricing, purchasing, inventory, quality and forecasting, and how they interact.
Core idea
The program asks each candidate to run a simulated lemonade stand for thirty in-game days and log every decision in a spreadsheet. The game is simple enough to play with children, but it packs in the core trade-offs of operations: what to buy, how much to stock, what recipe to use, what price to charge, and how to read demand from noisy signals like weather forecasts and customer feedback.
How it works
Each day the player:
- Reads the conditions: cash on hand, the forecast and the high temperature.
- Checks inventory: cups, lemons, sugar and ice. Ice melts every night; other supplies spoil more slowly.
- Makes acquisition decisions: how many of each to buy, at volume-dependent prices.
- Sets price and quality: price per cup, and lemons, sugar and ice per pitcher.
- Records results: cups sold, potential customers, customer satisfaction, popularity, and notes.
At season’s end: total income, total expenses, value of the liquidated inventory, and net profit or loss. Bankruptcy is possible; if it happens, the rule is to admit it and play again.
What players discover:
- Quality and price interact. Satisfied customers raise popularity, which raises future demand, so a stingy recipe can win today and lose the season.
- Inventory is a bet on demand. Over-buying perishable ice wastes cash; under-buying loses sales on hot days.
- Signals are noisy. Forecasts are wrong some of the time, so robust policies beat optimizing for each day.
- Record-keeping is learning. The spreadsheet turns guesswork into a running experiment (see PDCA Cycle).
In practice
The game is a miniature of real operating decisions in engineering businesses: lot sizes for long-lead parts, buffer stock against supplier variability, pricing a service against its quality, and reacting to demand signals without overreacting. Comparing logs with classmates (the program awards a prize for the highest profit) also shows how differently people interpret the same information.
Questions to ask yourself
- In my work, what is the equivalent of perishable ice: inventory or capacity that’s lost if unused?
- Do I set “price” and “quality” together, or optimize each separately?
- What does my own decision log tell me about how I respond to noisy signals?
Connections
- Real-world counterpart: Supply Chain Management. Variation and flow: Dependent Events and Statistical Fluctuation.
- Money side: Product Development Economics. Learning loop: PDCA Cycle.
- Capabilities exercised: Decision Making, Resourcefulness, Inquiry.
Sources
- Course exercise using an online lemonade-stand business simulation; no public source.