The reliability problem in grading teachers
A new study underwritten by the Bill & Melinda Gates Foundation (which is among the funders of The Hechinger Report) tackles the question of whether the new teacher evaluation systems going into effect in school districts across the country are accurate and reliable in identifying which teachers are good and which are not. The researchers found that the new evaluation systems are likely to be more reliable than the methods used in the past. But they are not perfect.
The study argues that current teacher evaluation systems are broken, suggesting, as many critics have in the past, that the problem with the old approach was its failure to distinguish among the great, the mediocre and the bad: More than 90 percent of teachers were labeled as satisfactory, even in school districts where student achievement and graduation rates were abysmal. Under the old system, principals usually conducted one classroom observation per teacher every few years, marking off things on a checklist, like whether students were behaving and goals were displayed on the chalkboard.
Advocates for a new system of measuring teachers—with usually more than one classroom observation a year, plus standardized test scores that measure how much a teacher’s students improve academically, plus other measures like student survey results—say it is more consistent and precise. This new system is being