Evaluation of Effectiveness: Nevada

Teachers should be judged primarily by their impact on students.

While many factors should be considered in formally evaluating a teacher, nothing is more important than effectiveness in the classroom. Unfortunately, districts have used many evaluation instruments, including some mandated by states that are structured, so that teachers can earn a satisfactory rating without any evidence that they are sufficiently advancing student learning in the classroom. It is often enough that teachers appear to be trying, not that they are necessarily succeeding.

Many evaluation instruments give as much weight, or more, to factors that lack any direct correlation with student performance—for example, taking professional development courses, assuming extra duties such as sponsoring a club or mentoring and getting along well with colleagues. Some instruments hesitate to hold teachers accountable for student progress. Teacher evaluation instruments should include factors that combine both human judgment and objective measures of student learning.

Evaluation of Effectiveness: Supporting Research

Reports strongly suggest that most current teacher evaluations are largely a meaningless process, failing to identify the strongest and weakest teachers. The New Teacher Project's report, "Hiring, Assignment, and Transfer in Chicago Public Schools", July 2007 at: http://www.tntp.org/files/TNTPAnalysis-Chicago.pdf, found that the CPS teacher performance evaluation system at that time did not distinguish strong performers and was ineffective at identifying poor performers and dismissing them from Chicago schools. See also Lars Lefgren and Brian Jacobs, "When Principals Rate Teachers," Education Next, Volume 6, No. 2, Spring 2006, pp.59-69. Similar findings were reported for a larger sample in The New Teacher Project's The Widget Effect (2009) at: http://widgeteffect.org/.  See also MET Project (2010). Learning about teaching: Initial findings from the measures of effective teaching project. Seattle, WA: Bill & Melinda Gates Foundation.

A Pacific Research Institute study found that in California, between 1990 and 1999, only 227 teacher dismissal cases reached the final phase of termination hearings. The authors write: "If all these cases occurred in one year, it would represent one-tenth of 1 percent of tenured teachers in the state. Yet, this number was spread out over an entire decade." In Los Angeles alone, over the same time period, only one teacher went through the dismissal process from start to finish. See Pamela A. Riley, et al., "Contract for Failure," Pacific Research Institute (2002).

That the vast majority of districts have no teachers deserving of an unsatisfactory rating does not seem to correlate with our knowledge of most professions that routinely have individuals in them who are not well suited to the job. Nor do these teacher ratings seem to correlate with school performance, suggesting teacher evaluations are not a meaningful measure of teacher effectiveness. For more information on the reliability of many evaluation systems, particularly the binary systems used by the vast majority of school districts, see S. Glazerman, D. Goldhaber, S. Loeb, S. Raudenbush, D. Staiger, and G. Whitehurst, "Evaluating Teachers: The Important Role of Value-Added." The Brookings Brown Center Task Group on Teacher Quality, 2010. 

There is growing evidence suggesting that standards-based teacher evaluations that include multiple measures of teacher effectiveness—both objective and subjective measures—correlate with teacher improvement and student achievement. For example see T. Kane, E. Taylor, J. Tyler, and A. Wooten, "Evaluating Teacher Effectiveness." Education Next, Volume 11, No. 3, Summer 2011, pp.55-60; E. Taylor and J. Tyler, "The Effect of Evaluation on Performance: Evidence from Longitudinal Student Achievement Data of Mid-Career Teachers." NBER Working Paper No. 16877, March 2011; as well as H. Heneman III, A. Milanowski, S. Kimball, and A. Odden, "CPRE Policy Brief: Standards-based Teacher Evaluation as a Foundation for Knowledge- and Skill-based Pay," Consortium for Policy Research, March 2006.