This is a very matter-of-fact description of what a seminar course session requires and how to offer it online. Here's what it requires (quoted):
- A prompt or text(s) that the student considers independently in advance
- Guiding questions that require analysis, synthesize and/or evaluation of ideas
- The opportunity to share personal thinking with a group
- Ideas being developed, rejected, and refined over time based on everyone’s contributions
Each of these is described in an online context in some detail. The considerations are worth reading, though I would prefer a slightly less prescriptive approach. But the main thing here is to focus on these four basic requirements and to think about how they can be supported online. Do you really need to have everyone go to a multi-million dollar building to do this?