This study examined the reciprocal dynamics of teacher autonomy support with student motivation and engagement during late elementary and early middle school. A total of 861 students in grades 5-7 reported on three components of teacher autonomy support (choice, relevance, and respect), as well as their own engagement and self-system processes (autonomy, competence, and relatedness) at the beginning and end of the same school year. Examination of feedforward effects showed that changes in aggregated teacher autonomy support predicted changes in all three self-processes and engagement; but feedback effects suggested that only student autonomy uniquely predicted changes in the autonomy support teachers subsequently provided. The three components of teacher autonomy support showed somewhat differentiated feedforward and feedback effects depending on the individual student outcome. Finally, person-centered analyses suggested that the effects of the components of autonomy support were cumulative. Together, such feedforward and feedback effects could create virtuous and vicious cycles that may contribute to the generation and maintenance of differentially motivationally supportive teacher-student transactions.