No. While there have been some lower courts which have held that the DOE’s own Manual of Pedagogical Observations acts as a rule or regulation which must be followed, the Appellate Division, First Department has held that observations, which normally require pre-observation conferences, are not required for a U-rating to be sustained.
Teacher observations are not a guide as to teaching quality or effectiveness. Here is a good discussion as to why.
http://teaching-abc.blogspot.com/2014/07/are-lesson-observations-worthwhile.html