The Impact of Teacher Evaluation and Development on Teacher Practice

The Widget Effect (Weisberg, Sexton, Mulhern, Keeling, Schunk, Palcisco, and Morgan, 2009)
While teacher evaluation systems should serve as the primary mechanism for assessing variations in teacher performance, in practice they have revealed little about how one teacher differs from any other. This report examines our pervasive and longstanding failure to recognize and respond to variations in teacher effectiveness.

Subjective and Objective Evaluations of Teacher Effectiveness: Evidence from New York City (Rockoff & Speroni, 2011) An analysis of diverse measures of teacher effectiveness in New York City.

Information and Employee Evaluation: Evidence from a Randomized Intervention in Public Schools (Rockoff, Staiger, Kane, Taylor, February 2011)
Research in New York City found that objective data on teacher effectiveness help principals support their staffs and have positive impacts on student achievement.