Development, implementation, and evaluation of a multilevel SEL program to promote caring communities in Greek schools

School-based interventions promoting social and emotional learning (SEL), positive behavior, and equity-oriented practices are increasingly recognized as important for preventing and addressing challenging and aggressive behavior. This study describes and evaluates Routes II, a multilevel intervention developed by the Laboratory of School Psychology at the National and Kapodistrian University of Athens to enhance school climate, supportive and cooperative relationships, and students’ social and emotional well-being. The program combined online teacher training and supervision, structured classroom activities, and an online networking platform. A mixed-methods design was used for the evaluation, which incorporated pre- and post-intervention surveys. Participants included 99 school administrators, teachers, and school psychologists and 843 students from 34 secondary schools across four Greek regions. Paired survey data were available for 37 teachers and 90 students. Teachers reported perceived improvements in caring-community climate, use of positive behavior and SEL techniques, and exploratory indicators of individual class goals. Students reported changes in negative classroom behaviors, but these were not statistically significant after Benjamini–Hochberg correction. Given the study design, findings reflect perceived changes and do not support causal conclusions. The study provides preliminary evidence of the potential of multilevel SEL-based interventions to support safe, supportive, and resilient school communities.