We've been in the Open Classroom for 4 years and have another child starting kindergarten in the fall. This has been a great program for our family. The Co-Op model allows us, as parents, to really get to know the teachers, the students, other parents and the administration. Spending a couple of hours a week in class with my daughter has given me insights into her strengths and weaknesses that no report card or parent-teacher conference could.
I recently saw some writing by a group of 3rd graders from the Open Classroom side by side with writing on the same topic by kids from other schools. The things which stood out were, Open Classroom kids had more spelling errors and their handwriting was not as neat, but the content of the writing was much more thoughtful and expressive. This sums up a lot of what I love about Open Classroom! Expression, thinking and communicating are valued above the mechanics of education.