There’s been much publicity (News & Observer) about a recent National Research Council study that says students taught by teachers with National Board of Professional Teaching Standards Certification (NBPTS) do better in school than those whose teachers are not nationally certified. Educators and teacher groups around the state are touting the study as proof that not only are North Carolina’s 12,770 nationally certified teachers making a difference, but also that the state’s 12 percent salary differential it awards to certified teachers is a good investment.
The study -- which included a large sample of NC students and teachers -- was intended to put to rest some of the questions that have hovered around the certification program. A closer look at the study and news reports suggests that results in North Carolina aren’t quite what we’ve been led to believe. Instead of answering these questions, the study may have only raised more. Education Week (6.18.08) reported that students with nationally certified teachers seemed to score higher than students with teachers without the credential. However when researchers analyzed studies, most of them struggled to assess the exact impacts of NBPTS.
'Most of the studies asked: When students have nationally certified teachers are test scores higher, and the answer is unambiguously yes,’ said panel member Mark Dynarski, a senior fellow at Mathematica Policy Research Inc, in Princeton New Jersey and director of the federal What Works Clearinghouse.
The committee struggled though over how to characterize the size of the programs impact on students’ test scores. In North Carolina, for instance, the effect sizes ranged from .04 to .08 – the latter translating to about 1 point on a test with a mean score of 150 (emphasis mine), according to the report.
On the question of what happens to teachers once they acquire NBPTS certification, Education Week continued…
While one study showed that board certified teachers were more likely to stay in teaching, data from North Carolina suggest, that once they achieve certification, they change jobs at a higher rate than do unsuccessful applicants for the credential. And when they move, the statistics show, they end up in teaching jobs where student achievement levels are higher and student poverty levels are lower.
The disappointing findings regarding student achievement scores and teacher migration raise obvious questions about the cost effectiveness of NBPTS. While the NRC study was unable to draw any firm conclusions about cost effectiveness, a few quick calculations might contribute to this discussion.
North Carolina has 12,770 nationally certified teachers. Staff at the Fiscal Research Office tells me NBPTS teachers received an average $527 more per month. On an average 10 month schedule, that’s $5,270 in additional NBPTS pay per year. A conservative estimate of annual state salary costs for 12,770 certified teachers is $67.3 million ($5,270 x 12,770). Sixty-seven million for a 1 point increase in student test scores? Does NBPTS really make a difference in NC? I’m not against teachers. However, I don’t think the NRC study can be used to tout the benefits of certification in North Carolina. If someone wants to forward evidence that this program is cost effective, I'm waiting.