School engagement has been proven to be a crucial factor in the development of a successful educational trajectory. It is a multidimensional concept encompassing affective, cognitive, and behavioral aspects, all of which are influenced by the social support students receive from the contexts in which they grow, with the most significant being family, teachers, and peers. The primary objective of this study is to analyze the impact of family, teacher, and peer support on students’ levels of affective, cognitive, and behavioral school engagement in the subsequent year while also examining variations between primary and secondary school students. This study involved 927 elementary and secondary school students who were assessed over two consecutive years. The results of the multigroup structural equation analysis revealed that family, teacher, and peer support levels had distinct predictive capabilities on different components of school engagement at both educational levels. Specifically, family support predicted levels of cognitive engagement, while peer support predicted levels of affective engagement. Furthermore, for elementary school students, teacher support emerged as a predictor of behavioral engagement, while for secondary students, it was identified as a predictor of cognitive and affective engagement. This study highlights how important family, teacher, and peer support are for shaping different aspects of school engagement. By understanding these distinct influences, educators and families can work together to create supportive environments that help students thrive academically and emotionally.