Experiments are deemed not only useful, but necessary in sustainability transformation to enhance local decision-making. This is especially apparent in Finland where national government programmes and city administrations promote sustainability experimentation and bottom-up initiatives in the interest of equitable participation. At the same time, universities are expected to respond to societal calls for major infrastructural transformations, while neoliberal principles shift responsibility from authorities to individual citizens. This paper examines the case of a student-driven sustainable campus initiative called “Test Site” in a university committed formally to sustainability education. The students questioned whether sustainability should be taught in air-conditioned classrooms, what topics were socially just and worth pursuing, and rather sought material engagement, creative exploration and autonomy. Invested faculty members were dependent on demonstrations and proof of impact, or at least convincing visuals, to sustain the initiative. The outcome of experimenting most valued by the students however was the material-based social learning on how to self-organise. The meaning of such “minor” experiments thus becomes muddled, involving local, situated power dynamics among university management, faculty and students and what is regarded as useful space and activity for learning. The case illustrates how an experimental site partly removed from university constraints rendered explorations of self-organising participants as valuable yet depended on visible proofs to justify this very exploration as worthwhile. Even within a neoliberal and highly hierarchical governance structure, some participants are able to make small gains to pursue socially just solutions.