The structure of relationships in the classroom and socio-emotionally proceeding in the learning environment may hinder or support children´s learning and development. Therefore, measuring the social climate is essential to identify challenges, successes, and areas for additional improvement. The present study examined the effect of a practice-based coaching intervention in improving the social climate in the learning environment and academic achievement and behavioral outcomes for students. The design was experimental with a cluster randomized assignment. Eligibility criteria for participants and clusters were 1) municipal primary schools, 2) second-grade classes, and 3) teacher certification. Intervention pertains to the cluster level: classes were N=4 and students N=66; wait-list-control group: classes were N=4 and students N=77. The duration of the intervention was five months. It consisted of three key components: action planning, observation, and professional conversation, according to the Practice Based Coaching model. The overall aim of the present study was to develop and test the effects of the intervention that involves the introduction of activities, self-assessment, observation, and coaching aimed at beneficially changing the social climate in the classroom, with a hypothesized indirect impact on students´ self-concept, prosocial behavior, well-being, and academic achievement. To investigate the immediate effects of the intervention, autoregressive structural equation models were estimated. The regression estimates of the intervention of the latent variables at the post-test were non-significant. Based on the obtained results, we discuss potential changes for a longer duration, more frequent coaching sessions, and additional instruments that might enhance the effect of the intervention changes without compromising its feasibility.