Students' perceptions of interactions with their teacher lay the stage for future interactions, ultimately influencing students' success in school. While prior work has elucidated what individual and contextual factors contribute to the development of middle and high school students' perceptions, less is known about elementary students' perceptions. As such, the present study leveraged a racially/ethnically diverse sample of third and fourth grade students and teachers in a large, urban district to investigate whether stable student and teacher characteristics (e.g., sex) and observed quality of classroom interactions influenced change in students' perceptions of interactions with their teacher. Results indicated that students rated their teacher more positively from Time 1 to Time 2 when female and in classrooms characterized by positive teacher-student interactions. Unexpectedly, students in classrooms characterized by high Instructional Support rated their teachers less positively over time. Implications for teacher-student relationships and students' academic and social-emotional achievement are discussed. [This paper was published in "Journal of Applied Developmental Psychology" v69 2020.]