"The Dirty Dozen: How Charter Schools Influence Student Enrollment," by Kevin Welner of the National Educational Policy Center, appeared in Teachers College Record. The journal article classifies 12 different approaches that charter schools use to structure their enrollment, which result in non-equitable opportunities for students. The practices range from "steering away less desirable students" to making parents pay hundreds of dollars in fines for behavior infractions such as not looking teachers in the eye.