After New York City encouraged principals to be more deliberative in awarding tenure, ineffective teachers were more likely to leave schools or the profession voluntarily—to the benefit of students, according to a recently released working paper.
The paper tracks the effect of a 2009-10 change in teacher evaluation policy in New York City. Principals were asked to weigh performance observations, reviews of teachers’ lesson plans, and, in limited instances, “value added” data based on test scores. Principals were also required to justify their decisions about whether to grant or deny tenure; they could put off the tenure decision for a year if they weren’t ready to make a final call.
The researchers found that far more teachers had their probationary period extended under the new policy, and the number of teachers approved for tenure dropped sharply. Teachers with an extended probation were more likely to move to a different school, or quit teaching in New York City, relative to tenured teachers in the same school. “Extended” teachers who chose to leave were less effective, on both principals’ judgment and value-added measures.