The Baltimore Sun posted an article last week looking into why Baltimore County teachers are leaving in higher numbers this year compared to last year. It quotes a teacher, the school system’s chief human resources officer, and the vice president of the Maryland State Education Association all speculating on why. It could be new teacher evaluations. It could be what the article calls the “flawed rollout” of new curriculum tied to the Common Core. Or it could be a change in benefits allowing teachers who retire earlier to pay less in health care costs.

Or it could be just statistical noise.

First, as the article buries somewhat, teacher retirements or resignations are actually down across the region. I put the Sun’s numbers in the table below to illustrate the regional totals. Overall, there have been 584 fewer departures this year than last, a decline of 24.1 percent. Baltimore County itself has 57 more departures than it did last year (an increase of 8.6 percent), but that still represents less than 10 percent of Baltimore County’s teacher workforce.

Second, new teacher evaluations, the Common Core, and the change in health care benefits are all statewide policies. None of these things are unique to Baltimore County, so it’s hard to believe they are responsible for its minor increase in teacher departures. Even if you believed Baltimore County’s rollout of new teacher evaluations and the Common Core were uniquely bad, you’re still stuck with the fact that these dramatic changes have led to a grand total of 57 additional departures. In a school system with 8,792 teachers, we’re talking about .006 percent of the district’s teaching workforce.

Ultimately, there are a number of factors that may affect teacher retention in any given year. We should be wary about trying to pin down any one reason, and we should be especially skeptical of narratives that try to explain small differences in a grand fashion.

-Chad Aldeman

This first appeared on teacherpensions.org