Assess students' ability to apply a simplified life-cycle assessment (LCA) to compare environmental impacts of single-use plastic, paper, and reusable shopping bags; require definition of a functional unit (e.g., one shopping trip or 1,000 uses), selection of life-cycle stages (raw material, manufacture, transport, use, end-of-life), choice of impact categories (GHG emissions, energy, water, waste), basic calculations or tabular comparisons using provided/assumed data, a short sensitivity analysis (e.g., reuse or recycling rates), and a concise interpretation with practical recommendations.