The problem with this is that when there is a reduced supply of teachers it costs money to find them and to cover the risk that the school won't be happy with them. (schoolsweek.co.uk)
Based on original research in four districts, we show that teacher cost averaging drives significant amounts of money (several hundred dollars per pupil in many cases) out of schools serving poorer students and toward better - off schools. (crpe.org)
Based on a massive study, Dr. [Raj] Chetty testified that a single year in a classroom with a grossly ineffective teacher costs students $ 1.4 million in lifetime earnings per classroom,» Judge Treu wrote in his 16 - page decision (pdf). (bloomberg.com)