This study examined the extent to which the quality of teacher-child interactions and children's achievement levels at kindergarten entry were associated with children's achievement trajectories. Rural students (n = 147) were enrolled in a longitudinal study from kindergarten through first grade. Growth trajectories (initial level and slope) were modeled with hierarchical linear modeling for 3 areas of achievement: word reading, phonological awareness, and mathematics. Cross-classified analyses examined the extent to which quality of teacher-child interactions and children's starting level predicted achievement growth rates over 2 years, and they also accounted for the changing nesting structure of the data. Results indicated that achievement at kindergarten entry predicted children's growth for all 3 outcomes. Further, first-grade teachers' strong emotional support related to greater growth in students' phonological awareness. Emotional and instructional support in first grade moderated the relationship between initial achievement and growth in word reading. Kindergarten classroom organization moderated the relationship between initial achievement and growth in mathematics. The implications of schooling for early growth trajectories are discussed. (Contains 5 tables and 3 figures.)