Having attended and / or taught several classes I have found that
hands on classes need to be limited to 10 to 12 people per instr.
I have taught innumerable classes, both ongoing and one-time ones
lasting from 3 hours to 3 days. I feel that the maximum number of
students depends VERY much on the subject/skill/project being taught,
the skill level and diversity of the students, and the equipment
available. There is no way to give a one-size-fits-all answer.
In a project class, where everyone is doing the same thing at the
same time, and there is no soldering, and everyone has the necessary
tools, I can shepherd 15 or more students successfully (as I will in
Santa Fe at BeadFest this week). I have had very successful classes
of this sort with as many as 21.
If there is soldering and the students are inexperienced, I stay by
each person’s side as they solder every seam, so I usually limit
those classes to 10 or so, though I have had as many as 15 and it was
still OK. They all learn a lot from watching each other learn. On the
other hand, these are classes of 3 to 6 hours to learn to make
something I can do in 10 minutes.
In an advanced weekly class where each student is working on
projects of their own choosing and needs/wants individualized help,
it can be exhausting to have even 6.
It just depends.