A paper presented yesterday at the Incentive Pay Conference held on campus raised some eyebrows. The authors looked at the relationship between teacher effectiveness and teacher retention -- in some contexts less effective teachers were more likely to leave a school while in others there was no statistically significant difference between more and less effective teachers.
The statistic that seemed to raise eyebrows was that after 5 years about 2/3 of the beginning teachers were still teaching at a public school in Florida (the paper examined 5 cohorts of first-year teachers in Florida public schools over 5 years). One economist suggested that this was a much higher retention rate than any other professional field and that, perhaps, we should be asking why so many teachers stay in the field instead of why so many leave.
The point raised is a valid one, it appears that teacher retention is not a problem in a lot of places and that, taken as a whole, there is no "teacher shortage" in this country. But there's a dangerous caveat that makes saying "teacher retention isn't a problem" just as false as saying that it is; teacher retention is a problem in some areas -- most notably high-poverty schools.
In this particular study, the authors found that only 20% of teachers in high-poverty schools were still teaching in that school in their fifth year and that teachers tended to transfer to schools with fewer minorities, fewer students in poverty, and higher test scores. To be fair, after reading the paper in full, the authors do acknowledge this -- but that doesn't change the fact that the reaction in the room seemed to be agreement that teacher retention was overblown as a problem in America's schools.
Secondly, the utility of an overall number is limited because it remains to be seen how much it helps or hurts a school when a teacher leaves one school in favor of teaching in another. Imagine the most extreme scenario: all teachers remain in teaching for their entire career, leading to an overall retention rates of 100%, but switch to a different school each year; even though teacher retention is not a problem for the system as a whole, it might be within schools.
There is no "teacher shortage" in this country, but some schools are short on teachers. Most teachers continue to teach, but not in certain schools. Teacher retention may not be a problem at the school down the street, but it may be at the school across town -- and dismissing it as a problem is just as dangerous as exaggerating the scope of the problem.