TEACHER TRAINING

Teacher Training

Teacher Training

Introduction

It is generally acknowledged that promoting teacher quality is a key element in improving primary and secondary education in the United States. Indeed, one of the primary goals of the No Child Left Behind law is to have a “highly qualified teacher” in every classroom. Despite decades of research, however, there is no consensus on what factors enhance, or even signal, teacher quality.

One reason for the uncertainty regarding the effects of teacher training is that past studies have been unable to overcome three methodological challenges in estimating the effects of training on teacher quality. First, it is difficult to isolate productivity, especially in teaching where a student's own ability, the influences of a student's peers, and other characteristics of schools also affect measured outcomes. The problem is exacerbated by the fact that assignment of students and teachers to classrooms is usually not random, leading to possible correlations between observed teacher attributes and unobserved student characteristics. Second, like in other occupations, there is an inherent selection problem in evaluating the effects of education and training on teacher productivity. Unobserved teacher characteristics, such as “innate” ability, may affect the amount and types of education and training they choose to obtain as well as subsequent performance of teachers in the classroom. Third, it is difficult to obtain data that provide much detail about the various types of training teachers receive and even more difficult to link the training of teachers to the achievement of the students they teach. Addressing all of these issues in a single study presents significant data and estimation challenges.

Teacher Productivity

In early work on teacher productivity, researchers estimated education production functions by regressing aggregate student achievement levels on measures of teacher training and various other controls using cross-sectional data (see review by Hanushek, 1986, 1141-77). A subsequent generation of studies used student-level two-year test-score gains and richer sets of teacher training variables to evaluate the impact of teacher training on student achievement. The state of the literature through the year 2000 has been extensively reviewed by Wayne and Youngs (2003, 89-112) as well as by Rice (2003), Wilson and Floden (2003), and Wilson et al (2001). Rather than duplicate previous surveys we highlight new research findings over the last half-dozen years.

While some recent studies of the determinants of teacher productivity continue to employ the gain score approach (Aaronson et al, 2007, 95-135; Hill et al, 2005, 371-406;, Kane et al, 2006), the bulk of recent research has shifted away from this methodology. The gain-score studies rely on observed student characteristics or “covariates” to account for student heterogeneity. However, they cannot control for unobserved characteristics like innate ability and motivation. There is evidence that better trained and more experienced teachers tend to be assigned to students of greater ability and with fewer discipline problems (e.g., Clotfelter et al, 2006, 778-820; Feng, 2005). Given this positive matching between student quality and teacher training, the gain-score studies' inability to control for unobserved student characteristics would tend to upwardly bias estimates ...