Faculty beliefs regarding the achievement potential of women and minority students may be communicated through microinequities in everyday exchanges. To determine whether women and minority students perceive a less encouraging classroom atmosphere than white male students, 941 students were surveyed using a questionnaire designed for this study. Results indicated that, overall, students perceived instructors as encouraging and welcoming comments or questions in class; however, minority students felt less encouraged than caucasians, women less than men, and undergraduates less than graduate students. A pattern emerged in which conscious efforts to affirm and encourage women and minority students were negated by nonconscious behaviors such as rarely calling on them, interrupting, using the generic he, and addressing the class as if no women or minorities were present. Although instructors were not viewed as being particularly partial to men, men reported being more likely to seek help from an instructor. The findings suggest that differential treatment may be a contributing factor in the lower academic aspirations of women and minorities. (The study questionnaire is appended.) (JAC)