The national social, emotional, and behavioral (SEB) screening in South Korean schools focuses on identifying and intervening with students at risk for SEB concerns, with little attention paid to students' SEB strength. This study aimed to examine (a) the technical adequacy of the Social Emotional Health Survey--Primary (SEHS-P), Youth Internalizing Problem Screener (YIPS), and Youth Externalizing Problem Screener (YEPS), (b) the relations of the YIPS and YEPS to students' subjective well-being (SWB) in schools, and (c) the incremental predictive utility of the SEHS-P for students' SWB in schools. Confirmatory factor and hierarchical multiple regression analyses were conducted using a sample of 790 fourth-sixth grade students in South Korea. Results supported the factor structures and reliability of the screeners and indicated that the SEHS-P explained significant additional variance in school-specific SWB beyond that accounted for by the YIPS and YEPS. Implications for future research and practice are discussed.