-The author review of the literature about the relationships among SES and educational outcomes revealed surprisingly few SES threshold studies relative to the enormous corpus of research on SES composition effects.
– With few exceptions, the very small number of U.S. studies that report thresholds effects typically were conducted by a school district’s internal staff using cross-sectional data (only one year) for a subpopulation of district’s students.
-Conclusions reached in these studies arguably apply only to the students in the district who took part in the study, in the year in which the data were collected.
-The studies described in this report are not an empirical foundation upon which general educational policy regarding SES thresholds can be reliably or validly based.
– Educational decision makers should focus on reducing concentrations of school-level poverty to as low a level as is feasible given the available demographic mix, and avoid policies based on the unsupported notion that there are poverty thresholds above and below which student achievement levels can be predicted.
– There is not yet a body of systematic, reliable, and valid evidence that school poverty thresholds exist, and that they influence student achievement outcomes.