"Freshmen who have many of their courses taught by adjuncts are less likely than other students to return as sophomores, according to a new study looking at six four-year colleges and universities in a state system. Further, the nature of the impact of adjunct instruction varies by institution type and the type of adjunct used, the study finds. And in some cases, students taking courses from full-time, non-tenure track instructors or from adjuncts well supported by their institutions do better than those taught by other kinds of adjuncts."