This paper uses rich new data on New York State teachers to: determine how much variation in the average attributes of teachers exists across schools, identify schools that have the least-qualified teachers, assess whether the distribution has changed over time, and determine how the distribution of teachers is impacted by attrition and transfer, as well as by the job matches between teachers and schools at the start of careers. Our results show striking differences in the qualifications of teachers across schools. Urban schools, in particular, have lesser-qualified teachers; and New York City stands out among urban areas. Low-income, low-achieving and non-white students, particularly those in urban areas, find themselves in classes with many of the least skilled teachers. Salary variation rarely compensates for the apparent difficulties of teaching in urban settings and, in some cases, contributes to the disparities.