J.C.
Hi C.-
There are a couple local Co-op preschools with which I have had great experiences. The Children's Workshop Co-op (aka Little Red Schoolhouse - http://www.thechildrensworkshop.org/index2.html) is right on School Street in Davisville and the Barbara Tufts (East Greenwich) Co-op (http://www.barbaramtufts.org/) is great, too. These schools are very reasonably priced (the latter is on a sliding scale) and I have really enjoyed being "Parent of the Day" and being involved in the classroom.
Good Luck with your decision!