Shanker Blog » The Allure Of Teacher Quality - 0 views
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Jeff Bernstein on 24 Apr 12Fueled by the ever-increasing availability of detailed test score datasets linking teachers to students, the research literature on teachers' test-based effectiveness has grown rapidly, in both size and sophistication. Analysis after analysis finds that, all else being equal, the variation in teachers' estimated effects on students' test growth - the difference between the "top" and "bottom" teachers - is very large. In any given year, some teachers' students make huge progress, others' very little. Even if part of this estimated variation is attributable to confounding factors, the discrepancies are still larger than most any other measurable "input" within the jurisdiction of education policy. The underlying assumption here is that "true" teacher quality varies to a degree that is at least somewhat comparable in magnitude to the spread of the test-based estimates. Perhaps that's the case, but it does not, by itself, help much. The key question is whether and how we can measure teacher performance at the individual level and, more importantly, influence the distribution - that is, to raise the ceiling, the middle and/or the floor. The variation hangs out there like a drug to which we're addicted, but haven't really figured out how to administer.