For the sake of argument, let's assume that it is important to rate teachers. Here I list Schank's criteria for rating teachers:
does the teacher inspire students?
does the teacher encourage curiosity?
does the teacher help students feel better about themselves?
does the teacher encourage the student to explore his or her
own interests?
does the teacher encourage the student to come up with his or
her own explanation for things they don't understand?
does the teacher set him or herself up as the ultimate
authority?
does the teacher encourage failure so that the student can learn
from his or her own mistakes?
does the teacher care about the students?
Really, how hard is it to recognize that these aspects of teaching are tremendously more important than test score improvement?