Douglas O. Staiger and Jonah E. Rockoff, "Searching for Effective Teachers with Imperfect Information," (Journal of Economic Perspectives, 24(3): 97–118, Summer 2010).
District leaders who don't know what to do with the immense amount of teacher quality and evaluation research to date would be wise to pick up this study. In it, the authors apply teacher quality indicators (like years in the classroom, decisions of tenure, and pre-hire evaluation tools) to the human resource practices of school districts, guided by a simple question: Based on what we know, how should districts recruit, retain, and fire teachers in an economically rational way? Keeping an eye on the bottom line, they run a few models, changing factors like the timing of tenure and the amount/quality of teacher evaluation tools available. They conclude that we should lower the bar for new applicants, since pre-hire information is poor, but significantly raise it for tenure, because the long-term cost of one bad teacher swamps the short-term cost of hiring a new one. (A Hamilton Project report from Brookings made a similar recommendation back in 2006.) In the meantime, the authors argue, investing in better pre-hire and on-the-job evaluation tools is worth the cost and bother because even just a little bit more information can fine tune the timing and levels of rigor exercised at each step of hiring, retaining, and firing.