Teacher Evaluations Found to Improve Midcareer Effectiveness

A new study, “Can Teacher Evaluation Improve Teaching?”, shows that Cincinnati’s rigorous Teacher Evaluation System (TES) has had a direct and lasting effect on midcareer teachers’ performance. Students taught by a teacher in the years after she had been through the evaluation program scored 0.11 standard deviations higher in math, on average, than the students she taught in the years before her evaluation (as measured by end-of-year 4th through 8th grade state tests). This difference is equivalent to about 3 - 4 months of additional instruction or a gain of about 4.5 percentile points for the average student. The Cincinnati evaluation is a yearlong process and a teacher’s students also scored 0.05 standard deviations higher in the year their teacher was being evaluated, a difference of 1.5 - 2 months of additional instruction.

Researchers Eric S. Taylor and John H. Tyler note that to the best of their knowledge, their study is the first to test the hypothesis that practice-based teacher evaluation programs can help to improve teacher performance, in addition to their value in identifying teachers’ strengths or weaknesses. Well-designed performance evaluation “can be an effective form of teacher professional development,” the authors observe.

In 2000, Cincinnati launched TES, a thorough process by which teachers’ performance is assessed through classroom observations and a review of work products. Teachers are observed and scored four times: three times by a peer evaluator (an experienced teacher) and once by a school administrator. Both peer evaluators and administrators complete an intensive training course, learning to accurately score videotaped teaching examples according to a specific rubric. TES is costly (about $7,500 per teacher evaluated, primarily for evaluators’ salaries) and its approach “contrasts starkly with status quo ‘principal walk-through’ styles of class observation,” note the authors.

Currently, all teachers newly hired by the Cincinnati school district, regardless of prior experience, take part in a TES evaluation during their first year. In their fourth year they are evaluated again, prior to receiving tenure (assuming successful evaluations), and once every five years after achieving tenure. For tenured teachers, evaluation scores determine eligibility for some promotions or additional tenure protection, or, in the case of very low scores, placement in a peer assistance program with a small risk of termination.

The researchers’ analysis includes only teachers hired before TES was introduced in the 2000-2001 school year and who were teaching 4th through 8th grade in the years 2003-04 through 2009-10. The group evaluated included 105 experienced teachers hired by the district in the school years from 1993-94 through 1999-2000. Evaluating this sample of teachers allowed the authors to measure the effect of evaluation on performance separate from any gains that come from increased experience, and permitted them to make comparisons of the achievement levels of a given teacher’s students both before and after the TES assessment.

The authors observe that the teachers in their study experienced their first rigorous evaluation after 8 to 17 years on the job, and may have been particularly receptive to comments from peer evaluators, rather than solely from administrators. The TES impact was found to be largest for teachers who were the weakest prior to evaluation. The researchers note that their findings suggest well-structured evaluation systems can be cost-effective expenditures that “not only serve (a) sorting purpose but also enhance education through improvements in teacher effectiveness.”