Which teachers remain teaching in their original schools, who transfers to other schools, and who exits teaching altogether obviously has implications for the quality of the teaching workforce. A new study conducted by Tim Sass and Li Feng examines how teacher quality (as measured by value-added data) and teacher mobility are related.
Analysts utilize teacher quality and mobility data in Florida from the 2000–01 school year to 2003–04. Specifically, they use matched student-teacher panel data that includes math and reading teachers in grades 4–10, for whom they have current and prior-year student achievement data.
They find that, for both math and reading, the average quality of teachers who stay at their initial schools is higher than teachers who switch schools within their initial district, move to another district, or leave public school teaching altogether. Moreover, better-than-average and worse-than-average teachers (those in the top and bottom quartiles, respectively) both have a higher likelihood of leaving teaching compared to middling teachers. Analysts say this is consistent with “schools losing their best teachers to more attractive outside options and losing their worst teachers who may be better suited to other occupations.”
They also find that, as the share of peer teachers with more experience, advanced degrees, or professional certification increases, the likelihood of moving within the district decreases. This suggests that peer teachers with better qualifications “may be more likely to provide positive spillovers or otherwise enhance the work environment.”
Next, they find that teachers overall tend to move to schools where students have higher achievement, a smaller fraction of students are black, and a smaller proportion of students are low income. Digging deeper, their results show that teachers who move tend to go to a school where the average teacher quality is like their own. For instance, the fraction of top-quartile movers hired by schools whose faculty is in the top quartile is much higher than that of schools whose faculty is in the bottom quartile. And the pattern continues as average teachers tend to move to average schools and bottom-quartile teachers tend to move to bottom-quartile schools. Case in point: Bottom-quartile schools disproportionately attract more bottom-quartile teachers (43 percent of transfers) compared to top-quartile schools (where 13 percent are bottom-quartile transfers). The net result of this movement of educators across schools? Differences in teacher quality are made worse.
We’re left with a mostly grim picture of how teachers choose to move around. Because even if we could finally figure out how to lure more effective teachers to the places that need them the most (more cash anyone?), there’s a strong possibility that once there, they could leave again if their new crop of colleagues aren’t up to their standards.
SOURCE: Li Feng and Tim Sass, “Teacher Quality and Teacher Mobility,” Education Finance and Policy (Summer 2017).