Abstract
BACKGROUND: This project evaluates the effectiveness of the Norwegian version of Second Step Early Learning (Nor-SSEL), a translated and culturally adapted Norwegian version of the American Second Step program, compared to free play in kindergartens, in a cluster-randomized controlled trial. Nor-SSEL is a socio-emotional learning (SEL) program that spans 28 weeks, emphasizing the development of learning skills, friendship skills, and emotional management. We hypothesize that Nor-SSEL is superior to free play in enhancing children's social-emotional learning (SEL). METHODS: We will allocate 990 children within 66 kindergartens, which will be randomized at the kindergarten level. The primary outcome is child psychosocial adjustment, assessed using the Strengths and Difficulties Questionnaire (SDQ), as reported by parents and teachers at baseline, immediately after the 28-week intervention in the kindergarten, and then 7 months after the transition to the new school (K1). The secondary outcome is empathy, assessed using the Empathy Questionnaire for Children (EmQue), which parents and teachers report at the same time points as the SDQ. Mediator analysis will be explored using the Joint Attention Scale, and as the moderator, we will analyze the parents' socioeconomic status. A distal exploratory variable in follow-up assessment is academic achievement at the end of the first grade (math and reading skills). To reduce missing data, a web application will be developed to track children's behaviors via teachers, parents, and children's activities. DISCUSSION: We believe that the Nor-SSEL impacts the joint attention score, which, in turn, affects the SDQ score. This study contributes to the scientific understanding of how the SEL curriculum intervention can impact SEL and future academic achievement in kindergarten-aged children. This could shape early education policies and practices in kindergartens, as well as their potential application to social, emotional, and academic skills. TRIAL REGISTRATION: ClinicalTrials.gov NCT06975267. Registered on 16 May 2025. https://clinicaltrials.gov/study/NCT06975267 .