Association for Public Policy Analysis & Management

States and school districts frequently seek approaches to enhance teachers’ knowledge, skills, and the quality of their instructional practices.  While education officials and practitioners have instituted many policies and reforms towards this end, one long-standing approach has been to incentivize teachers to acquire additional credentials that may improve teaching.  Most notably, many states and school districts provide permanent salary increases for teachers that earn a graduate degree or become Nationally Board Certified (NBC).  In recent years, however, these pay increases for graduate degree holders have faced critical attention as states and school districts experience financial shortfalls and research questions the impacts of graduate degrees (Chingos & Peterson, 2011; Clotfelter, Ladd, & Vigdor, 2007, 2010; Sorensen & Ladd, 2015). 

More than ever, high-quality research evidence is needed to better understand the impact of graduate degrees on a range of teacher outcomes.  This is particularly important since research on graduate degree impacts has generally been limited in two ways:  (1) researchers have focused on value-added rather than a more comprehensive set of teacher outcomes and (2) researchers have estimated overall impacts of graduates degrees, rather than estimating results for specific graduate degree content areas.  This is especially salient, given policies that may reward teachers for earning graduate degrees in their area of teaching.

To address these limitations, I use data provided by the North Carolina Department of Public Instruction and the University of North Carolina system to examine teacher value-added, evaluation ratings, and persistence and to code graduate degrees in four ways:  (1) overall; (2) timing (graduate degrees earned pre- and post-entry into teaching); (3) content-area (graduate degrees in particular content or grade-level areas); and (4) in-area (graduate degrees in teachers’ area of teaching).  I perform value-added and persistence analyses using data from 2005-06 through 2012-13 and evaluation rating analyses from 2010-11 through 2012-13. 

In comparison to teachers with undergraduate degrees only, I find that, overall, graduate degree holders are significantly less effective in six of ten value-added comparisons.  However, teachers with a graduate degree in their area of teaching are more effective in mathematics.  Furthermore, in middle and high school grades, teachers are often significantly more effective after they earn a graduate degree in their area of teaching than they were prior to graduate degree completion.  Across all five teacher evaluation standards, graduate degree holders earn significantly higher evaluation ratings and while graduate degree holders are more likely to exit teaching in North Carolina, overall, those with a graduate degree in education, rather than a content-area, are more likely to stay. 

There are three key takeaways from this analysis:  (1) overall, differences between graduate degree holders and undergraduates are relatively small in magnitude; (2) graduate degrees in teachers’ area of teaching have positive impacts on student achievement and teacher development; and (3) outcomes for graduate degree holders do not lend themselves to straightforward policy prescriptions—efforts to reward effective teachers and incentivize teachers to pursue additional learning will require nuance and a thorough understanding of the research evidence.