This paper reflects on how the transformative potential of public spaces can catalyze collaboration between universities and peripheral contexts. Starting from the role of reactivated disused urban spaces towards fostering social innovation in neighborhood as well as new forms of experimental learning for university students, it presents the ongoing case study of an interstitial space regenerated by a research team to become a meeting ground between students and the local community.

Off Campus Nolo (OCN) is one of four Off Campus spaces of the Politecnico di Milano, an initiative promoted by the Social Responsibility Projects Service that aims to bring teaching and research into direct contact with marginalized territories. OCN is in the Nolo neighborhood of Milan, a dynamic, responsive, and contradictory area, and is part of its Municipal covered Market. There we developed "OUT. Il Cortile Sociale" (OUT): an interstitial space reactivated through a collaborative effort between the university, the municipality administration and local associations. Despite its transformative potential, the Municipal Market courtyard was a disused space, serving as a garbage collection area. In 2023 OCN and the Polimi DESIS Lab research team supported its regeneration and reactivation, guiding three local associations in signing a “Patto di Collaborazione” (Collaboration Pact) with the Municipality to take care of the space over time. After a light spatial renovation, OUT was inaugurated and local associations, in synergy with OCN, took charge of animating it with social, artistic, and cultural activities. Today OUT is an accessible public space with a flexible layout capable of hosting various types of activities and local events.

The paper presents the methodology applied in the courtyard reactivation and the actors involved, subsequently delving into the activities that generated interactions between Politecnico di Milano students and the local community.

In particular, the study focuses on three key activities conducted in this space, which differ in the level of informal involvement of students and local actors:
1. The “Designing in a Multispecies World” Design Course (Politecnico di Milano, School of Design, A.Y. 2023-2024): the courtyard, together with OCN, became the headquarter for multidisciplinary students exploring the neighborhood and presenting to local community their projects.
2. The "Ab-OUT green" event during Milano Green Week 2023: a co-design and participatory setup action for greenery within the courtyard that involved neighborhood residents to foster a sense of stewardship and responsibility towards the courtyard, with a formative moment that involved residents, Politecnico students, and local schools.
3. A meeting with the “Service Design Drink Milan” community, where the courtyard became an opportunity to weave new relationships by exchanging experiences and knowledge.

Analyzing these activities, the paper highlights the added value of such hybrid experiences in accessible public spaces, which connect academic learning with community engagement. Additionally, the role of OCN in conducting responsible research and innovative teaching, returning a social public space to the local community and experimenting with new methods of engagement and learning for students, is discussed. The findings suggest that spaces like OUT. Il Cortile Sociale can enhance educational outcomes, promote inclusivity and strengthen university-community ties.

Keywords: University-community collaboration, public spaces reactivation, participatory design process, experiential learning.