Assess students' ability to apply life-cycle assessment (LCA) and cost–benefit analysis (CBA) to evaluate environmental and economic trade-offs between single-use and reusable coffee cups in a university setting. Scope: define a functional unit, map life-cycle stages (materials, manufacture, transport, use/cleaning, end-of-life), compile inventory data, calculate key impacts (e.g., GHG, water), monetize costs and externalities, run sensitivity/threshold analysis on reuse rates and cleaning regimes, and present evidence-based recommendations with clear assumptions and uncertainty discussion.