Douglas N. Harris and Tim R. Sass
National Center for Analysis of Longitudinal Data in Education Research
March 2007
In the No Child Left Behind era, teachers who achieve certification from the National Board for Professional Teaching Standards are supposed to be the most qualified of "highly qualified" teachers. It ain't necessarily so, says this appraisal of the effectiveness of NBPTS-certified teachers in reading and math. The study finds that, while many teachers who obtain NBPTS certification are superior to their peers who do not, they lose some of their edge after receiving certification. In particular, math teachers who become NBPTS certified end up being more effective with high-achieving students yet retain no margin of difference from their non-certified peers when working with students of low socio-economic status. This raises the question: Is NBPTS certification worth the time and money teachers and states and Uncle Sam and umpteen foundations have put into it if the benefits don't accrue to students who have been "left behind"? The study also suggests diminished returns over time. Specifically, teachers who received certification in NBPTS's early years (before 2001) remain more productive post-certification than their non-certified peers. By contrast, teachers in the 2002 and 2003 cohorts are no more productive post-certification than their non-certified peers. Could that be because there are so many more of them? In so many more fields? Has quantity sapped quality as NBPTS has grown? Board-certified teachers now get almost $1 billion annually in bonuses and salary enhancements. But are kids really benefiting from this investment? Find the study here.