In recent years, scholars have begun to document the emergence of private migrant schools in urban China. However, neither education nor labor scholars have empirically investigated teachers’ work. Because it is precisely those with the fewest economic resources that have been restricted to privatized education in the city, migrant schools are dependent on a highly exploitative form of employment. Based on a study of Guangzhou and Beijing, we see that there is diversity in working conditions. In Beijing, teachers are subject to extralegal precarity in which basic legal enforcement is tenuous to nonexistent. In Guangzhou, there is greater legal compliance, but management has employed market discipline to shift risk onto teachers. In general, teachers’ work in migrant schools is similar to other forms of migrant labor in China, characterized by low pay, long hours, high work intensity, and lack of job security. The article concludes by assessing the divergent politics of migration in each city while considering the implications for socioeconomic inequality.