Business schools have a responsibility for educating global citizens capable of understanding and addressing the major societal challenges of the 21st century. However, working on complex societal problems within business school curricula remains a challenge. This teaching brief presents a learning project that helps instructors introduce systems-thinking skills into the classroom to address complex problems of sustainability. The project involves students studying an issue of their choice within one of the 17 UN Sustainable Development Goals and designing a multi-stakeholder strategy to both alleviate problem symptoms and address their underlying causes and drivers. Analysis of student evaluations and feedback show that the project engages students and favors systems-thinking skill acquisition. The project can be run either online or in the classroom, individually, in small teams, or with an entire class. It can be used by instructors for sustainable development, corporate social responsibility, and systems-thinking classes, or be run as a capstone activity.