Does the poverty level of a school impact how much a teacher improves (or not) over time? Analysts at CALDER sought the answer by studying elementary-school math teachers (at the fourth- and fifth-grade levels) in self-contained classrooms in North Carolina and Florida over time (eleven years for North Carolina and eight for Florida). The bottom line: They found no systematic relationship between school-poverty rates and how teachers performed over time as measured by value-added scores. In both high-poverty schools (over 60 percent students receiving a free or reduced-price lunches) and lower-poverty schools (fewer than 60 percent), teacher performance improves fastest during the first five years, then flattens out. (Yes, we’ve heard this before!). Teacher performance growth resumes between years 10 and 15 in North Carolina but remains flat in Florida. Throughout, the analysts found significant differences among teachers in improvement over time. In each of the three career stages examined (novice, early, and mid-career), the fastest-improving teachers gain the equivalent of more than half a year of performance growth annually than the slowest improving teachers. But again, these differences are not correlated in any systematic way with the poverty status of the school—which means that working in a high-poverty school does not necessarily impact the growth rates of teachers.
SOURCE: Zeyu Xu, Umet Özek, and Michael Hansen, “Teacher Performance Trajectories in High and Lower-Poverty Schools,” Working Paper 101 (Washington, D.C.: National Center for Analysis of Longitudinal Data in Education Research, American Institutes for Research, July 2013).