Social-emotional learning (SEL) curricula, such as Second Step, are increasingly being adopted and implemented as universal supports in schools in order to prevent social-emotional and behavioral problems and promote wellbeing and success. Notwithstanding the empirical support for SEL as a universal prevention strategy, a closer look at the literature indicates that students display differential responses to SEL based on their behavioral functioning at baseline; those students with the highest need benefit the most from SEL. The primary purpose of this study was to evaluate whether a widely-adopted SEL program produces significant effects for different theoretically-constructed groups of students who are representative of the full spectrum of students in a school. Using data from a large-scale randomized controlled trial evaluating Second Step, analyses examined the extent to which group membership according to the dual continua model of mental health differentially changed based on whether the student was in the intervention or control condition. Overall, results evidenced significant effects favoring the intervention condition across groups in line with our general hypotheses, although both conditions experienced transitions in membership. As expected, those in the intervention condition experienced greater transition between groups, which was indicative of either treatment or prevention effects. Implications, limitations, and future directions of the findings for SEL programming in schools are discussed.
Keywords: Dual continua; Mental health; Population effects; SEL; Universal prevention.