This study aimed to design and refine a music curriculum that integrates Social and Emotional Learning (SEL) into fourth-grade classrooms through rhythm composition. SEL has been widely recognized as a key foundation for children’s mental health, social competence, and lifelong well-being (CASEL, 2020). Given that music education inherently involves emotional expression and social interaction, it provides a powerful and authentic context for developing SEL skills (Hallam, 2010; Jellison, 2015; Rickard & McFerran, 2012).Although Taiwan’s Ministry of Education began promoting SEL in 2025, it has not yet been systematically incorporated into the national curriculum, resulting in limited teaching resources and pedagogical models for classroom practice. With support from the Kaohsiung City Government, a professional learning community (PLC) of music teachers was established to collaboratively design, implement, and refine the curriculum through two iterative cycles of the Plan-Do-Study-Act (PDSA) model (Deming, 1993). After implementing the curriculum in the first class, the researcher revised and refined it based on feedback from the teacher community. The revised version was then applied to a second class, leading to the finalized curriculum. The six-week program guided students to create “emotional rhythm chants.” They began by recalling their own negative emotional experiences and discussing possible coping strategies with peers. Eventually, they transformed these reflections into personalized rhythmic and verbal expressions—individual emotional rhythm chants.The curriculum was structured to progress from emotional self-awareness to emotional self-regulation, followed by self-observation and peer observation. Students completed an Emotional Self-Awareness Form before the first week of instruction, an Emotional Regulation Strategies Form after the sixth week, and both Self-Observation and Peer-Observation Forms two weeks after the course ended. These instruments were used to analyze students’ development and changes in SEL competencies.Music learning and SEL complemented each other in this study. Music activities enhanced students’ SEL skills, while SEL concepts enriched their musical creativity. Through peer interaction and reflection, students developed empathy, teamwork, and communication skills, and learned to apply these abilities in real-life contexts.Findings showed clear improvement in students’ emotional awareness, self-regulation, collaboration, and empathy. The results highlight music education as an effective pathway for fostering SEL, offering a feasible and inspiring model for integrating emotional learning into elementary music classrooms in Taiwan. This study also underscores the potential of music education to promote students’ emotional well-being and holistic growth within a global educational context.keywordsSocial and Emotional Learning (SEL)Professional Learning Community (PLC)Plan-Do-Study-Act (PDSA) model