The School of the Prophets was established and held in the upper room of the Newel K Whitney Store in Kirtland, Ohio during the winter of 1832-1833.
In his talk, A Principle With a Promise, President Ezra Taft Benson describes the conditions and dimensions of this room as a little under 11'x14'.
My students measured and taped off an area that was this size and then I asked them to sit shoulder to shoulder during our lesson.
If I had access to picnic benches for them to sit on, this would have been even more effective.
This is a great setting for teaching the introduction to the Word of Wisdom or any other lesson/principles taught at the School of the Prophets.