Study for NBPTS Raises Questions About Credential

Certified Teachers Lack an Edge; Board Won’t Release Full Report

Teachers certified by the National Board for Professional Teaching Standards are for the most part no more effective in producing student academic progress than teachers without the special status, a long-awaited study concludes.

The research, which draws on one of the largest data sets used so far to examine the credential, was completed well over a year ago. But the board did not provide any public information about the less-than-flattering portrait until earlier this month, when an “overview” was posted on the organization’s Web site. And it put out the summary only after being pressed by a prominent education blogger. National-board officials say they do not intend to release the full study.

Conducted by William L. Sanders, the statistician who pioneered the concept of “value added” analysis of teacher effectiveness, the study found that there was little difference in students’ achievement levels for teachers who earned the prestigious NBPTS credential, those who tried but failed to earn it, and those who never tried...