Despite its many advantages, teaching transdisciplinary is a costly enterprise. Transferring diverse theoretical, methodological, and practical skills may require several teaching staff; developing meaningful stakeholder interaction is time-intensive; and managing the research process demands significant efforts in logistics and coordination. This article seeks to make two distinct contributions. Conceptually, it introduces a framework for distinguishing between soft, inclusive, reflexive, and hard transdisciplinarity, based on the notion that there are diminishing returns to all features of the practice. Empirically, it examines a classroom simulation – the Sustainable Development Indicator Exercise (SDIE) – as an example of soft transdisciplinarity. In the SDIE interdisciplinary student groups play the role of policy advisers. Building on a concrete transdisciplinary research project, they explore their understanding of sustainability, develop a multi-criteria decision making method for assessing sustainability criteria and indicators, elaborate and present their results, and reflect on their experience. All aspects of the exercise follow the logic of role playing: organizing group interaction, distributing responsibilities, interacting with their political principal, presenting their findings, and evaluating their progress. Experience from the simulation reveals insights into ways students address and express concerns with objectivity, transparency, deliberation, and balancing sustainability; it also points to ways for moving beyond soft transdisciplinarity.