Research on charter schools tends to focus on direct and immediate effects on student outcomes. However, there may be unintended indirect effects on, for example, the teacher labor market. Charter schools tend to hire teachers with fewer traditional teaching credentials, which may reduce the equilibrium quantity of teachers who have traditional credentials and seek to make teaching a career. We test whether charter entry reduces the supply of university teacher education degrees, exploiting within- and between-district variation in the timing of charter school entry in districts containing college teacher preparation programs. Applying a generalized difference-in-difference model, we find that a 10 percent increase in charter market share decreases the supply of traditionally prepared teachers by one percent per year on average. This effect is concentrated in elementary education and special education degrees, which, anecdotally, are less valued in charter schools.

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特许学校入学对大学教育项目教师供应的影响

对特许学校的研究往往侧重于对学生成绩的直接影响。然而，这可能会对教师劳动力市场等产生意想不到的间接影响。特许学校倾向于聘用具有较少传统教学资格的教师，这可能会减少具有传统资格并寻求以教学为职业的教师的均衡数量。我们利用包含大学教师培训项目的地区内和地区之间特许学校入学时间的差异，测试了特许学校入学是否会减少大学教师教育学位的供应。应用广义双重差分模型，我们发现特许市场份额每增加 10%，传统教师的供应量就会平均每年减少 1%。这种影响集中在基础教育和特殊教育学位上，据说这些学位在特许学校中不太受重视。