Low-inference classroom observational data were collected on 362 children in four elementary schools (grades two to five) who had been consistentlV ranked by two successive teachers over a two-year period. Teachers ranked students on one or more of thirteen bipolar scales assessing personality characteristics and teacher expectations. Two-way analyses of variance were employed using grade and sex as classifying variables. Results indicated that although teachers generally responded similarly to both sexes, subtle differences emerged in terms of differential patterns of teacher-student interaction, especially in response opportunity styles, private work contracts, differential acceptance of child-initiated, nonacademic requests, and both the teachers' and the students' affective responses to the dyadic interactions. Differences among grades indicated a shift from a private to a public focus, with more interactions being work centered. These differences were discussed in terms of maturation and increased socialization of the students to teacher expectations. (Author)