One of the traditional complaints about charter schools is that they have high teacher turnover.  Particularly when hired through alternative channels (such as Teach for America), many critics believe – and several studies have borne out – that charter teachers leave the profession faster. But what is often not clear is why this is so.

The Center for Reinventing Public Education (CRPE) did an comprehensive study on the difference between the two models, looking at 956 charter and 19,695 traditional school teachers hired in Wisconsin between 1998 and 2006.  The lessons from the study may not hold true everywhere, and much has changed since that time period, but they offer a good starting point to examine this issue in more depth.

First, as with other studies, CRPE found that there was indeed more attrition at charter schools. However, they also looked deeper.  First, they controlled for individual characteristics (age, gender, academic degrees, etc).  This initial difference shrunk.  They then controlled for school characteristics (student demographics, location, etc) and the difference disappeared entirely.  Once the researchers controlled for both individual and school characteristics, there was no longer a statistically significant difference between charter and traditional teachers.

They did find something that contradicts conventional wisdom. For among the statistically significant findings: charter schools were better at retaining teachers in urban schools:

Teachers working in urban charter schools in Wisconsin also appear less likely to switch schools and exit the system compared to teachers who work in urban traditional public schools.

Part of the antiquated system that has long contributed to the decline of urban education is the tendency of teachers to leave schools with the most challenged students populations for schools with greener pastures.  Far too many school systems are complicit in a pattern where the teachers with the least experience are disproportionally assigned to the toughest urban schools.

What’s particularly troubling to me in this debate is the way charter critics have seized on the issue of teacher attrition to deride young people who enter the teaching profession through alternative channels specifically to serve in some of the most difficult urban environments.  TFA has been the particular subject of ridicule — despite new studies showing that the vast majority of TFA teachers serve well beyond their initial two-year commitment.

And throwing stones is particularly bold from the glass traditional schools where fully half of new teachers leave the profession within five years.  The summary of the CRPE study makes a valuable point:

…policymakers might help all public schools by better targeting resources (both financial and human capital) to schools that arguably need them the most—those that enroll the most underserved students—be they charter schools or traditional public schools.

As with so much else, the myth of charter attrition obscures the very real challenge of trying to attract and retain great teachers to urban schools, and all too often prevents us from confronting a system where urban students are systematically disadvantaged.