We investigated college students' perceptions of instructor unfairness and their emotional and behavioral reactions to perceived injustice. Results obtained from 397 undergraduates from three universities in the United States indicate that anger and dissent were the strongest emotional and behavioral responses to injustice. Furthermore, disgust mediated the influence of injustice on student behaviors most damaging to professors--taking action, expressing verbal aggression, and dissenting to authority. Stress mediated the effect of injustice on the most constructive student behaviors--changing their approach and engaging in the class. We discuss the implications of the results of our study for the student-instructor relationship and learning in the contemporary higher education environment.