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Adam Kho

Adam Kho, Ron Zimmer, Andrew McEachin.

One of the controversies surrounding charter schools is whether these schools may either “cream skim” high-performing students from traditional public schools or “pushout” low-achieving students or students with discipline histories, leaving traditional public schools to educate the most challenging students. We use these terms strictly for brevity and acknowledge that many of the reasons that students are labeled high- or low-performing academically or behaviorally are beyond the control of the student. In this study, we use longitudinal statewide data from Tennessee and North Carolina and linear probability models to examine whether there is evidence consistent with these selective enrollment practices. Because school choice programs managed by districts (magnet and open enrollment programs) have a similar ability to cream skim and pushout students, we also examine these outcomes for these programs. Across the various school choice programs, magnet schools have the most evidence of cream skimming, but this might be expected as they often have selective admissions. For charter schools, we do not find patterns in the data consistent with cream skimming, but we do find evidence consistent with pushout behaviors based on discipline records. Finally, some have raised concerns that students may be pushed out near accountability test dates, but our results suggest no evidence consistent with this claim.

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Adam Kho, Gary T. Henry, Ron Zimmer, Lam Pham.

Many districts and states have begun implementing incentives to attract high-performing teachers to low-performing schools.  Previous research has found that these incentives are effective.  However, effects on the schools and students these teachers leave behind has not been examined.  This study focuses on the general equilibrium effects of recruiting effective teachers to Tennessee’s Innovation Zone (iZone) schools, one of the most successful turnaround initiatives in the nation (Zimmer, Henry, & Kho, 2017).  While there is some variation in the effects of losing these teachers, we find they range between -0.04 and -0.12 standard deviations in student test score gains.  However, an estimate including both these negative effects and the positive effects in iZone schools yields overall net positive effects.

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Samantha Viano, Lam Pham, Gary T. Henry, Adam Kho, Ron Zimmer.

Recruiting and retaining teachers can be challenging for many schools, especially in low-performing urban schools in which teachers turn over at higher rates. In this study, we examine three types of school-level attributes that may influence teachers’ decisions to enter or transfer schools: malleable school processes, structural features of employment, and school characteristics. Using adaptive conjoint analysis survey design with a sample of teachers from low-performing, urban, turnaround schools in Tennessee, we find that five of the seven most highly valued features of schools are malleable processes: consistent administrative support, consistent enforcement of discipline, school safety, small class sizes, and availability of high-quality professional development. In particular, teachers rated as effective are more likely to prefer performance-based pay than teachers rated ineffective. We validate our results using administrative data from Tennessee on teachers’ actual mobility patterns.

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Gary T. Henry, Lam Pham, Adam Kho, Ron Zimmer.

A growing body of research evaluates the effects of turnaround on chronically low-performing schools. We extend this research to formally test factors that either mediate or suppress the effects of two turnaround initiatives in Tennessee: the Achievement School District (ASD) and local Innovation Zones (iZones).  Using difference-in-differences models within a mediational framework, we find that hiring highly effective teachers and employing effective principals partially explain positive effects of iZone interventions.  In the ASD, high levels of teacher turnover suppress potential positive effects after the first year.  In iZone schools, several factors suppress even larger positive effects: hiring more novice teachers; hiring more principals with less experience; and high levels of student chronic absenteeism and student in-migration. 

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