School canteens hand out huge amounts of single-use plastic every day — wrappers, cutlery, bottles and bags that are used for minutes and discarded for centuries. Students see the overflowing bins but rarely have a system that makes reuse the easy, default choice.

Design a reusable lunch system that cuts single-use plastic waste in schools. Study who is affected, dig past the obvious symptoms to the real root causes, and design a solution that could actually work in the real world. There is no single correct answer — what matters is the quality of your thinking, the stakeholders you consider, and how clearly you justify your chosen direction.

• Who is most affected by this problem, and how did you account for them?
• What is the single biggest risk to your solution working?
• Which assumption, if wrong, would break your whole idea?