With teachers being increasingly evaluated on the basis of their students’ improvement on standardized test scores, it’s time to take a closer look at the process of class assignments.
Let’s be frank: If teachers happen to inherit a class of Talmudic scholars, chances are that they will receive a high rating because these students learn in spite of their effectiveness - not necessarily because of it. Conversely, teachers who are assigned a class of future felons are not likely to get the same rating. That’s why it’s so important to randomly assign students if fairness in evaluating teachers is a consideration. Unfortunately, the way most schools handle the issue does not engender confidence (“Dread of August: The Kids’ Teacher Assignments,” The Wall Street Journal, Aug. 6).
Researchers have long emphasized that random assignment of students is the sine qua non of instructional evaluation. “Non-random assignment of teachers can bias value-added estimates of teachers’ causal effects” (“Student sorting and bias in value added estimation: Selection on observables and unobservables,” The National Bureau of Economic Research, Jan. 2009). But instead, principals typically keep a tight rein on which teachers get which students. During my 28-year career, I saw how vocal parents who were active in school activities almost always were granted their requests for specific teachers. I also saw how favored teachers were given easy-to-teach students as a reward.
I see nothing at all wrong with parents submitting information about the needs and interests of their children. This can be extremely helpful in matching students with teachers. But when parents refuse to accept the final assignment and threaten to go over the head of the principal, they have crossed the line. Teachers find themselves in the middle of this kind of dispute. They want parental support, but they expect their principal to adhere to the class assignment policy. They’re right.