Here's what I think is out there about this issue. There was a study called Project Star done in Tennessee in 1985 over 4-years which did find that class size did matter. And, from a op-ed from Oregon Live by an Oregon state professor:
"Interestingly, the studies of the Tennessee experiment have found a clear rejection of the notion that a teacher aide can offset the effect of a large class: test results were statistically equivalent across large classes with and without an aide."
"A second study by the same team revealed that the positive effects from small classes in K-3 remained pervasive two full years after students returned to regular-size classes."
Here is a good article from the Department of Education on this issue.
Another article shows a map of class sizes throughout the country.
A professor from Northwestern University found that children did do better in smaller classes overall but that high achievers did the best and so the achievement gap did continue to exist.
I remember that when my kids were at Whittier that we used money in the budget (there was no I-728 then) to keep K-2 at about 20-21 kids (Helen S, is that your recollection as well?). I thought this was a great idea especially for little kids with their first school experience and that it was the crucial learning to read time.
I have always had it on the back burner to get the the root of the I-728 money. I know that it comes and goes in size and that it gets used for all kinds of things. Clearly, voters and parents thought we would get smaller class sizes out of it but here in Seattle, at least, it hasn't. I'll have to try to get this figured out.
For me, the bottom line is reality. A good teacher can handle a bigger class, sure. A bigger class for a mediocre or poor teacher is likely a disaster.
But c'mon, studies aside, we're all human beings. We know, without being a teacher, that having a smaller class allows the teacher to know the students better (especially their learning styles) and be able to help them more easily. It has got to be a lot less likely for the kid who is quiet and behaves to fall through the cracks. Overall, it just has to be easier for a teacher to do his or her best job with fewer students.
I don't care what Dr. Goodloe-Johnson says. Class size does matter (or it sure does to parents and I bet it will matter to her once her own child starts school). But it's all about money. Article after article talks about the difficulty of finding the money. And I have no idea how to solve that issue.