In their defence of the school Jan Masschelein and Maarten Simons define it as a source of 'free time.' Drawing on Catherine Malabou's compelling reading of Heidegger in her "The Heidegger Change," I aim to provide a strong ontological justification for the claims made on behalf of the school concerning free time, common goods, and renewing (changing) the world: the school provides free time; it transforms knowledge and skills into common goods; and it has the potential to give everyone the time and space to renew the world. The paper enquires into what 'free time as non-productive time,' 'common goods,' and 'changing the world' mean on an ontological register, and why therefore the school is so precious and warrants our utmost care in the face of its conservative and progressive critics alike. I discern a single underlying notion, the notion of essence as "mutability," constituting the link connecting free time, common goods, and renewal of the world.