Assess students' understanding of the physical and chemical processes driving ocean acidification (CO2 uptake, carbonate–bicarbonate equilibrium, pH and aragonite/calcite saturation states), natural and anthropogenic drivers (rising atmospheric CO2, upwelling, freshwater inputs), and the ecological and physiological impacts on marine organisms (reduced calcification, altered metabolism and behavior, developmental and food‑web effects) with examples such as corals, mollusks, pteropods, phytoplankton and fish; include interpretation of simple pH/pCO2 or saturation-state data and brief discussion of mitigation and adaptation concepts.