This paper presents a study focusing on the use of class time by minority students in junior high school science classrooms. An instrument was developed to assess classroom behaviors and the interactions of students, which was used to obtain information about classroom behaviors that might affect minority student outcomes in science. Students from a desegregated urban school district were observed by trained observers using the developed instrument to gather information about the interactions of subject students (N=52) with target students (several hundred) and six teachers at four different junior high schools. Results indicate: (1) that the instrument could be successfully used to record students' behaviors and interactions; (2) that very few cross-race interactions occur, even in an activity-oriented classroom; (3) that the frequency of attending behaviors was greater than the frequency of non-attending behaviors for male students of both races; (4) that no significant differences exist between black male students and white male students in classroom behavior patterns; and (5) that the average final grade for black male students was lower than the average final grade for white male students. (CS)