One of the group members suggested this topic: how groups form, how people are "assigned" a role within a group, when a group transitions to a team, etc.
The bad news for all of us is that my Masters is in this field of study, so I can shed some light on what to do...and maybe more importantly, what not to do in a group formation dynamic. I'll also cover some of the pitfalls groups encounter, which is so frequently overlooked.
The setting is both now - getting a group together - and post event and getting a group together in that environment.
Note, this will not be a lecture!