A school or district admin creates Department groups for a team, grade level or committee that wants its own room. Posting reuses the exact Post pipeline families already know, reactions, comments, moderation, so it's a real live feed, not a bolted-on bulletin board, and what staff post in a Department group never reaches parents.
Apptegy's Materials Hub and Finalsite Resources both sell a document library as their own product. Bloomz's version is organized in folders and carries a visibility setting per resource, staff-only or member, so a staff handbook and a shared class resource can live in the same tool with the right audience for each. The same library works for a class, school or district group, not only staff.
A staff-only Department group whose posts never reach parents, with a folder-based Materials Hub for staff-only and member resources.
Bring your hardest scenario, a multilingual community, a PBIS rollout, a vendor consolidation, and we'll walk through the actual product.