I've been teaching in Bahrain for a wealthy children of royals. It ironically turns out that this level of wealth has the exact same results as being poor. The student apathy about homework and attendance. The same attitude towards authority. The same immaturity. So I've been working with difficult students that are just as challenging as an inner-city urban school in the U.S. However, though one set of students is unhappy because they only get parental attention from their nannies, the other is helping feed the family while trying to study. So after working with problem students, I've decided that a good class size should be around eight students. Six, if they're difficult.
With that small of a group, everyone is focused, but the group is big enough to feel enough intellectual diversity to allow students to find their comfort zone and to get stimulation from their peers (no pun intended - that's a whole n'other set of discussions). However, the size of the class also allows the teacher enough time with each student that they really understand how each student learns and have the space to do that.
So, and this is the important part:
It would eliminate many of the SPED, administration, and consulting jobs in school systems, freeing up funds to hire more teachers. And the teachers would feel less stressed because not only would there be more of them, creating a stronger support network and less hours, but the paperwork loss alone would allow for more hours a week to do their jobs of planning, grading, and teaching. And teachers would be better at their jobs because they'd have more classroom and creative energy to offer their schools. Which means less accreditation stress and homework for the staff. And student's scores would improve, so the school would get more funding from the government. Allowing them to hire more teachers.
I think we're doing it wrong.