Purpose: This paper aims to show how the Green Campus Program has been implemented at the Faculty of Sociology of the University of A Coruña (Spain). It describes the criteria used to create teaching sustainability actions related to community engagement to introduce education for sustainable development into college curricula. Design/methodology/approach: Drawing on a human-centered design model approach, as well as on transformative teaching theories, this study explores the criteria used to build the Free Classroom based on a participatory model. Findings: The authors argue that the success of this activity depends on how it relates to the theme-based specialization of the different academic degrees through which they are managed. Equally important is the creation of permanent spaces that enable the collaboration of other organizations, such as non-governmental associations and local public administrations. Originality/value: The findings provide valuable insights into how the social dimension of sustainability in higher education institutions can be emphasized. A model of implementation of the activities is offered under which academic, political, student and community agents are coordinated to favor the change of attitudes and behaviors to strengthen SD.