Four combinations of teacher verbal and nonverbal evaluative behavior were studied within a controlled microlesson. Two male and two female teachers presented each of the four combinations--(a) verbally and nonverbally positive; (b) verbally positive and nonverbally negative; (c) verbally negative and nonverbally positive; or (d) verbally and nonverbally negative--to different, randomly selected samples of sixth-grade male and female subjects. Data analysis indicated that negative teacher nonverbal behavior led to significantly greater performance during the lesson. Teacher verbal behavior also influenced subject performance, interacting with the factor of individual teacher. On the measure of learning, females achieved significantly higher scores and teacher sex interacted with student sex. (Author)