While universal school-based social and emotional learning (SEL) programs claim to target various SEL competencies, earlier reviews have not provided a clear overview of the competencies in question. We therefore wished to identify the competencies targeted in SEL programs for secondary school students. We also aimed to examine the effects of these programs on SEL competencies and psychosocial health. The specific SEL competencies directly addressed in the programs' primary learning targets were identified based on the Collaborative for Academic, Social and Emotional Learning (CASEL) framework for SEL. Five bibliographic databases (PubMed, PsychINFO, Education Resources Information Center (ERIC), Applied Science Premier (ASP), and Web of Science) were searched for relevant research papers published between 2014 and 2018. We included 40 studies that investigated 32 programs focusing on two or more SEL competencies. While most programs targeted four or five of the SEL competencies, many of the included studies did not measure the programs' effects on all the competencies targeted. Our results showed that the SEL programs had substantial effects on the SEL competencies they addressed and on psychosocial health. Although the programs focused predominantly on self-management skills and relationship skills, the largest summary effects were found for self-awareness and social awareness.