I feel your pain. I just got kicked in the proverbial nuts on my annual performance review because the lesson I was observed teaching was, well, not "standardized" and did not have anything near a common assessment. The children in my second grade classroom told me at the beginning of the year they wanted to learn about ocean animals. So one week in November I obliged. I wrote up a series of lessons and taught them about some of the ocean animals that they mentioned having the most interest in. Stupid me, I chose one of these lessons for my admin to observe me teach. I didn't get through all of it, time ran out, so some standards were not observed and thus the closure did not match some of the stated objectives. Therefore, I have been scored as "Developing" and run the risk of being placed on a teacher improvement plan. Never again do I show my administration my creative side. School is like what you described. And I love your line about collaboration; it is really does seem like it's more enforcement of the established norm than anything else.