The classroom behavior of 92 black and white sixth graders was observed in a desegregated urban school. Observations were made once a week during a full semester. The sex and race of each student observed and of his or her interactants were noted. Observers also coded characteristics of observed students' interactive behaviors: the tone (positive, negative, or neutral), the form (physical or other), the source (the subject, interactant, or both), and the task orientation (whether or not the behavior was related to academic tasks). Students interacted primarily with others of their own race and sex although gender aggregation was less pronounced among blacks than among whites. Boys interacted more across racial lines than did girls. Blacks were almost twice as likely as whites to be the source of cross-racial interactions. Students' interracial behavior was generally not different in quality from intraracial behavior, although some potentially important differences between black and white children's behavior styles were observed. These conclusions were reinforced by a parallel study of sociometric choice conducted in the same school. (Author/MK)