Although the role of school engagement in influencing children's academic competence has been recognized in past theory and research, how school engagement may mediate the relationships between ecological and personal resources and academic competence remains largely unknown. Using structural equation modeling procedures, the present study was aimed at examining the role of school engagement in mediating the associations between ecological and personal assets and academic competence. Data from 960 participants (45.6% boys) who took part in the Grades 5 and 6 assessments of the longitudinal, 4-H Study of Positive Youth Development were used. Evidence was found for a model positing two distinct school engagement components, Behavioral and Emotional, and for the role of these facets of school engagement in the relationships between developmental assets and later academic competence. Personal and ecological assets had indirect effects on later academic competence, via behavioral and emotional school engagement. Behavioral and emotional school engagement predicted academic competence differently. Emotional engagement was indirectly linked to academic competence, via behavioral engagement. Behavioral and emotional engagement also had different individual and contextual antecedents. Implications of the findings for evaluating the role of behavioral and/or emotional school engagement in academic competence and positive youth development are discussed.