The goal of this chapter is to provide a cohesive developmental framework and foundation for which to understand student engagement across early childhood, middle childhood, and adolescence. Guided by the bioecological theory of human development and the person-environment fit perspective, this chapter extends Finn's participation-identification model of engagement by mapping student engagement within a larger developmental sequence. This chapter discusses student engagement within specific developmental periods that are tied to the developmental tasks, opportunities, and challenges unique to early childhood, middle childhood, and adolescence. Student engagement is found to be a nuanced developmental outcome, and the differences may be a result of the maturation of biological, cognitive, and socioemotional developmental tasks and the changing contextual landscape for the children and adolescents. Recommendations for future research as well as policy implications are also discussed.