One of the criticisms of measuring teacher quality with test scores and value-added measures is that test scores don’t measure learning that really matters, in particular that whatever test scores do measure isn’t something that lasts. However, there is increasing evidence that teacher quality measures really do–imperfectly–tell us about longer term outcomes. New work by Master, Loeb, and Wyckoff begins to parse out which measured effects last and which don’t. Here’s a quick summary. I’ve divided the authors’ results into ones that accord well with my intuition and those that I find more surprising.
- Good English language arts (ELA) teachers have a long-term effect on math outcomes.
- ELA teachers who themselves have stronger academic backgrounds produce more persistent gains.
Kind of surprising:
- Good math teachers do not have much long-term effect on ELA outcomes.
- ELA teachers in disadvantaged schools produce less persistent gains.