Duke Researchers Find Effective Teachers Clustered in Tested Grades

A recent working paper from public policy researchers at Duke University examines one potential unintended consequence of the school accountability era: Is it possible that accountability testing, which under No Child Left Behind begins in the third grade, has given elementary school administrators an incentive to cluster their strongest teachers in third, fourth and fifth grade classrooms, thus depriving younger students of more effective teachers?

According to the study, by Sarah C. Fuller and Helen F. Ladd, this may be the case. In North Carolina between the years of 1995 and 2009, teachers who were average or less effective at improving test scores were more likely than their peers to be reassigned from 3^rd-5^th grade classrooms to kindergarten, first grade and second grade. A teacher one standard deviation above the mean for student test scores in reading was 74.5 percent as likely as an average teacher to move from teaching 3^rd-5^th grade to teaching earlier grades. Teachers with above-average math scores were 70.1 percent as likely as an average teacher to move down into the early grades.

The practice of assigning the most effective teachers to the later elementary grades is of particular concern because gains made by children in high-quality preschool programs tend to “fade out” during the early elementary school years if children do not receive effective instruction during kindergarten, first and second grades.

North Carolina invested heavily in early education during the years covered by the study. Fuller and Ladd looked at standardized test data from both NCLB reporting and North Carolina’s pre-NCLB statewide accountability program, called the ABCs. The researchers found that K-2^nd grade teacher quality, measured in terms of teachers’ scores on licensing exams, fell short of teacher quality in the later elementary grades in all the years studied, not just in the years after accountability testing. Beginning in 2003, however, this shortfall became statistically significantly larger than it had in the past -- an indicator that the sanctions threatened by No Child Left Behind led principals to strategically assign their best teachers to the later grades, in order to raise test scores.

Only the more affluent schools, defined in the study as those with a low proportion of students receiving free and reduced-priced lunch, were engaging in the practice of clustering effective teachers in later grades before the accountability era began. The chart below, taken from the study, breaks down schools in different income groups by the shortfall in the licensure test scores of early elementary teachers. After accountability, all schools were engaged in the practice to roughly the same degree, regardless of the number of poor students attending the school:

From "School Based Accountability and the Distribution of Teacher Quality Among Grades in Elementary School." Note: FRL stands for students on Free- and Reduced-Price Lunch,  a common indicator of poverty. Click for larger image.

These findings can serve to complicate and enrich the discussion around how to best prepare teachers for the early grades. If trends like this one prove more widespread, it may be advisable to incentivize the placement of effective teachers in early childhood classrooms.