Teachers who qualify for national certification do a measurably better job in the classroom, according to a major study released last week.
Pupils of teachers certified by the National Board for Professional Teaching Standards (NBPTS) improved an average of 7 percent more on their year-end math and reading tests than pupils whose teachers attempted but failed to gain certification.
And, the study found that nationally certified teachers bestowed even greater benefits on younger and lower-income students.
“Our findings show that these teachers are more effective,” said Dan Goldhaber, a research associate professor at the UW’s Evans School of Public Affairs and affiliated scholar of the Urban Institute. He presented the results at the American Education Finance Association annual meeting.
The study — funded by the U.S. Department of Education and based on an analysis of more than 600,000 North Carolina elementary test scores — could put to rest some of the controversy in education circles surrounding the national certification.
Since the mid-1990s, more than $350 million has been spent on NBPTS certification, without clear research showing whether the more effective teachers were getting certified.
To find out, Goldhaber and co-author Emily Anthony of the Urban Institute, analyzed 609,160 year-end test scores of North Carolina third, fourth and fifth graders from 1996-97 to 1998-99. Each student was matched up with that year’s teacher.
Even after factoring out such characteristics as teachers’ experience, degree level and scores on licensing exams, teachers who met national certification criteria gave their students a small but statistically significant edge over students taught by unsuccessful NBPTS applicants.
And NBPTS teachers’ performance advantage was found to be largest for younger and low-income students. For instance, in reading, it rose to as much as 12 percent for the youngest students in the study (third graders) and to 15 percent for low-income pupils.
These results are consistent with decades of research showing that teacher quality has more impact on lower-achieving students than on high achievers.
One policy implication, Goldhaber said, would be a call for school districts to do more to entice their nationally certified teachers into classrooms with younger and more disadvantaged students.
The NBPTS program was launched 17 years ago by school reformers seeking a way to identify and reward teachers who could demonstrate excellence. Applicants undergo an evaluation that includes written examinations, lesson portfolios and classroom videos, and fewer than half of North Carolina’s applicants succeed on their first try. Critics have said there is no proof all this effort guarantees classroom superiority. Despite the controversy, NBPTS has certified more than 32,000 teachers across the nation since the mid-1990s and the number of applicants continues to rise.
Previous attempts to measure these teachers’ effectiveness relied on relatively small samples, but Goldhaber and Anthony drew on test scores from three grade levels of an entire state to document that the assessment process does select for teaching skills that actually help children learn.
“Our research does not show that the assessment process itself makes teachers better,” Goldhaber said, “but it does appear useful in identifying who the more effective teachers are.”
Is identifying the best teachers worth the national assessment program’s public and private costs, which include more than $200 million spent to develop the certification program, another $150 million spent on assessing teachers, and millions more paid in salary bonuses to those who achieve national certification?
“That depends on many factors,” Goldhaber said, “not least of which is whether receiving NBPTS certification helps to keep effective teachers in the classroom — particularly in classrooms that need them the most.”
The study is available online from the Center on Reinventing Public Education at www.crpe.org. The Urban Institute, a nonprofit, nonpartisan research institute in Washington, D.C., is on the Web at www.urban.org. More information about the National Board and NBPTS certification is at www.nbpts.org.