Student and investigation
Investigation question: How does changing one booth decision affect profit and at least one customer, capacity, or waste measure?
1. Plan a fair comparison
Independent variable—the one decision I will change:
Controlled variables—the decisions I will keep the same:
Prediction: If I change __________ from __________ to __________, then __________ will change because:
2. Estimate unit economics and break-even cups
Use the simulator estimate before opening. Contribution per cup is price minus ingredient cost per cup. Break-even cups equals fixed daily costs divided by contribution per cup.
Reasonableness check: Can your booth make and serve at least this many cups? ☐ Yes ☐ No ☐ Unsure
3. Record baseline and test evidence
Use days with similar forecasts when possible. Do not claim the changed variable caused everything: weather and random variation also affect demand.
| Run | Weather | Price | Quality | Batch | Helpers | Promotion | Cups sold | Waste | Lost customers | Profit |
|---|---|---|---|---|---|---|---|---|---|---|
| Baseline | ||||||||||
| Test | ||||||||||
| Repeat |
Profit difference between baseline and test:
Evidence pattern: Which metric changed most consistently?
4. Explain the result
Claim: Which decision was stronger for this booth?
Evidence: Cite at least two numbers from the table.
Reasoning: Explain how price, demand, cost, capacity, or waste connects your evidence to the claim.
Tradeoff or uncertainty: What became worse, or what else might have affected the result?
Next controlled test:
Teacher guide: 30-minute controlled experiment
- 5 minutes: introduce contribution per cup, fixed cost, break-even cups, and the difference between revenue and profit.
- 5 minutes: pairs choose one variable, record controls, calculate a break-even estimate, and make a prediction.
- 12 minutes: run a baseline and controlled test. Repeat if weather differs substantially.
- 5 minutes: write a claim using two numbers, one tradeoff, and one model limitation.
- 3 minutes: compare why the highest price, largest batch, or most helpers did not always create the highest profit.
Suggested discussion answer: a strong strategy balances contribution per cup with demand and makes enough product for likely sales without paying for excess capacity or waste.
Responsible-use reminder: the simulator omits many real food-safety, permit, allergen, tax, labor, cash-handling, and school-supervision requirements. Students should identify at least one missing real-world constraint.
Quick 8-point rubric
- Plan (0–2): one testable change, useful controls, and a reasoned prediction.
- Evidence (0–2): complete results with correct revenue, cost, profit, and break-even evidence.
- Reasoning (0–2): numbers support the claim through a plausible business relationship.
- Reflection (0–2): identifies a tradeoff, uncertainty, real-world limit, and useful next test.
Need more detail? Use the complete 16-point business simulation assessment rubric, teacher resource hub, or student business calculators.