ABSTRACT Research has established the importance of social-emotional learning (SEL) in traditional public schools, but not cyber schools. In this correlational regression study, we use students (n = 18,206) from a national cyber charter school network to examine whether items in the Collaborative for Academic, Social and Emotional Learning (CASEL) SEL index inter-correlate in cyber schools, and whether CASEL has statistical relationships with club membership, synchronous class attendance, and academic outcomes. Cross sectional analyses find that for cyber charter students, CASEL individual items correlate with each other, and that CASEL from 1st semester (T1) to 2nd semester (T2) correlates at .63; thus, CASEL may have reasonable reliability for cyber students. Yet, in contrast to physical schools, CASEL does not correlate with SEL-related variables like club attendance and synchronous class attendance and has a weak (though positive) relationship with cumulative grade point average (GPA), suggesting important differences from its application in physical schools. Ordinary Least Squares (OLS) regressions examining SEL associations with relevant demographic intersectional characteristics reveal that Black students perform similarly to other students, but that Free and Reduced Meal (FARM) and especially Individualized Education Plan (IEP) students have lower measured SEL. Using OLS regression to examine relationships between students’ GPA and demographic characteristics (controlling for CASEL) show that generally, FARM and IEP students have lower GPA, but Black students have the same mean GPA as others, and Black students with IEPs actually have higher than average GPAs. We discuss implications and directions for future research.