Differing Conclusions on the impact on National Board Certified teachers on student achievement

Two recent CALDER working papers, "The Effects of NBPTS-Certified Teachers on Student Achievement" by Douglas N. Harris & Tim R. Sass (Florida) and "How and Why Do Teacher Credentials Matter for Student Achievement?" by Charles T. Clotfelter, Helen F. Ladd & Jacob L. Vigdor (North Carolina) report somewhat divergent findings on the efficacy of the National Board for Professional Teaching Standards certification process.

This from CALDER.

CALDER (The National Center for Analysis of Longitudinal Data in Education Research) capitalizes upon longitudinal individual-level student and teacher data across a number of states, to investigate how state and local policies, especially teacher policies, governance policies, and accountability policies affect teachers (e.g., who teaches what students) and students (e.g., academic achievement and attainment).