Every week before class began, some students and I would rearrange the room from the traditional rows to a U-shaped set up. This allowed participants to see each other -- and engage in conversation -- without having to turn around or talk to each others' backs.
On the last night, when we had all student presentations, we left the classroom in its original format. What a difference it made. There was no engagement. There was a great deal of chatter and distracting side conversations from the back row. There was an air of formality instead of collegiality that had been present in the other class sessions.
We took a moment to pause and reflect on the difference the classroom set up made. Yes, it was a hassle to rearrange at the beginning and to reset at the end, but it made it a better class. I wonder why classrooms aren't set in a discussion-mode by default.
Think carefully about the setting where you want learning to occur. A U-shape is much better than rows. A round table beats rectangular by eliminating the "head" spot. An open square has different dynamics than a smaller table where participants are in close proximity to each other. A podium creates a barrier between the class and the presenter.
It can be easier to leave the set up as you find it, but it is exponentially worth using your brawn to benefit your brain through reconfiguration.