Participation is a key issue in understanding didactic dynamics. On the one hand, youth participatory cultures are described as incorporating gaming, multitasking, transmedia navigation and networking; on the other hand, the pre-digital meaning of participation retains a political value related to individual commitment for the common good and to socio-constructivist learning design. There is a connection among community, participation and learning, as the tradition of communities of practice highlights (Wenger, 1998, 2000). The present article introduces and discusses the results of the research focussing on the course for civil protection operators engaged in voluntary public assistance service. The course was delivered online following the lockdown measures enacted in response to the SARS-CoV-2 pandemic. Three specific dimensions were examined: (a) the trainer's role; (b) group dynamics; and (c) online participation. It was possible to compare these data with those collected in occasion of other training courses delivered face to face before the 2020 healthcare emergency. The research was conducted as a multimethod case study using quantitative and qualitative tools.