The School Lunch Tray: Waste, Equity and Hygiene
At a subsidised secondary school in Sha Tin, 900 students eat lunch on campus. A waste audit found 310 kg of food waste per week, mostly rice and vegetables; 35% of students leave at least half their tray. The current supplier charges HK$24 per meal and uses single-use plastic trays because the school kitchen has no industrial dishwasher. A parent group proposes switching to a local social enterprise that uses reusable trays and offers smaller portion sizes, but the price rises to HK$27 and the school must install a HK$150,000 dishwasher. The supplier warns that a price rise may push 80 low-income students to opt out. The green club wants a compulsory 'clean tray' scheme; teachers worry about supervision time. The school has a surplus of HK$400,000 but also needs to repair two laboratory fume cupboards. The principal asks the sustainability committee for a decision before the next tendering cycle.
1. Which two values are in conflict in the choice between the current supplier and the social enterprise? Explain with reference to the figures.
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The conflict is between affordability/equity and environmental sustainability plus health. The current supplier keeps the meal at HK$24 and avoids a HK$150,000 capital cost, which matters because 80 low-income students might opt out if the price rises to HK$27. But the school is generating 310 kg of food waste a week, and 35% of students leave at least half a tray; single-use plastic trays add to the waste stream. The social enterprise offers smaller portions and reusable trays, which could cut both over-serving and plastic waste, but the higher price and dishwasher cost shift burdens onto the school and poorer families. There is also a hygiene dimension: reusable trays require reliable washing and drying, or the environmental gain creates a food-safety risk. So the choice is not 'green versus wasteful'; it is a distributional choice about who pays for a lower-waste lunch system.
2. Recommend a decision to the principal, including whether to make the 'clean tray' scheme compulsory.
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Recommendation: adopt the social enterprise for a one-term pilot, with a targeted subsidy and a voluntary 'clean tray' scheme that becomes compulsory only if the pilot meets its targets. The school should use part of its HK$400,000 surplus to cover the HK$3 daily gap for the 80 low-income students, and to install the dishwasher; without that, the price rise would undermine equity. Smaller portions should be offered as a default with an option to ask for more, because 35% leaving half a tray suggests over-serving rather than simply fussy eating. The 'clean tray' scheme should start voluntary with class-level feedback, because a compulsory scheme adds teacher supervision time and may punish students who need help. The laboratory fume cupboards are a safety issue too; the committee should ring-fence at least HK$150,000 for them and not treat the whole surplus as available for lunch. A pilot allows the school to test waste reduction and opt-out rates before locking into a multi-year contract.
3. Explain how the school could measure whether the decision has worked after one term.
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The school should set a baseline before the pilot and compare after one term. Useful indicators include: food waste per student per week (target: reduce 310 kg by at least 25%), percentage of trays with more than half left (target: below 20%), number of students opting out for cost reasons (target: no increase from the current level), cost per meal to the school and to families, supervision minutes per class, and hygiene complaints or incidents. It should also survey students on whether they can get enough food, since smaller portions could reduce waste while leaving some hungry. A before-and-after comparison is stronger if the school tracks the same classes and keeps the menu similar. If waste falls but opt-outs rise, the pilot has not succeeded on equity; if opt-outs are stable but waste does not fall, the problem may be menu design rather than tray type.