Class Size - Does it matter? YES!

I do not get it.  My Finnish colleagues do not get it. 

Why can't U.S. policy makers and administrators understand the obvious challenges of larger classes and the educational impact of smaller classes? 

Some people say there is no definitive data -- something else for me to research or to substantiate...

This past fall, I had four classes of 35 students in Chicago.  The last year I was in the classroom, I had three classes of 37 students.  How do we expect teachers to (1) know their students' strengths and needs well and (2) plan & teach engaging, inquiry-based lessons effectively?

Here, almost all of the classrooms I have visited have 18-22 students with a couple that had 24 students (There were also several classes with less than 18).  Every mathematics lesson I have observed thus far, the teacher presents the theory and/or examples and then gives the students time to work.  Then the teacher circulates the room checking-in with each student 2 and often 3 times to check for understanding and clarify misconceptions.

That is the most consistent practice and, I would argue, most effective formative assessment I have seen.   As the teachers consistently shared in interviews and I witnessed in each classroom - the teachers know their students.  No standardized assessment would ever give this timely, accurate information as the teacher assessing each student, each lesson.

So how about connecting some dots... standardized tests cost millions of dollars annually.  Smaller class size means more teachers would need much more investment of funds.  So why can't we reduce and prioritize all the required standardized tests and invest the savings in smaller class size?  Am I mistaken?  I have the impression that we talk about these issues separately and they are so interconnected -- testing, class size, & instructional time.