I'll bet you are on to something. It's really sad to have all that MAP info and not be using it. Can you talk to the principle and see if he or she is interested? Perhaps you can get Winebrenner to come work with the school as part of the continuing education budget? Is there someone at a state level win the education department who could be a resource? Do any of the neighboring schools use cluster grouping and MAP and you could set the two principles up to chat?
Remember that cluster grouping only is proven to have educational effects when the teachers actually teach to the groups new higher readiness level.
Our state law requires parent representatives on the School Based Decision Making Councils. I got elected on a platform which included using MAP data results to help each individual student achieve growth goals. The school council has the responsibility to set school policy and make decisions to enhance student achievement so I'll be meeting with the principal monthly. After nearly two years of asking as "just a parent" for the SBDM to get and review this data, the principal finally came through with it after the election.
Thanks for the suggestions and your point about teaching to the new higher readiness level is key. I think this helps explain why some of the grades have a high percentage of students meeting the growth goals while other grades are much lower. Even though the classes are "balanced" the teachers in some of the grades cluster between their classes for part of the day to teach to the readiness level.
