Teachers may fail with junior high school age and black students because these groups differ from their senior high school age and white counterparts in their perceptions of which teacher behaviors are important. To test this hypothesis, black and white ninth and twelfth graders were asked to select their three best and three worst teachers and state what they considered to be the most important behavior differences between each good and each bad teacher. The 8640 identified behaviors were categorized according to three general dimensions: warmth, organization, and stimulation. Blacks and ninth graders more frequently perceived warmth factors as important, while for whites and twelfth graders organization and stimulation factors were more important. The 20 specific behaviors most frequently perceived as important were identified. Eighteen of these differed significantly by race or grade level. However, in terms of rank order listings, four of the top five behaviors for each group (ninth grade whites, ninth grade blacks, twelfth grade whites, twelfth grade blacks) were identical: (1) ability or willingness to adequately explain material; (2) ability to present material interestingly; (3) willingess to help students with work; (4) caring attitude. (Author/MC)