Global curriculum reforms increasingly emphasize the development of twenty-first century competencies—collaboration, communication, creativity, and critical thinking. Traditional subject-based teaching may not be sufficient to prepare students for complex social challenges, while cross-curricular approaches, particularly through STEAM (Science, Technology, Engineering, Arts, and Mathematics), provide opportunities to integrate music education into broader frameworks of learning.This study explores the role of music in cross-curricular contexts by applying Basil Bernstein’s pedagogic discourse theory and Pierre Bourdieu’s concepts of cultural capital and field. Bernstein’s distinction between collection and integrated codes highlights how disciplinary boundaries may be reconfigured in classroom practice, while Bourdieu’s framework clarifies how social and cultural backgrounds shape students’ capacity to engage with integrated learning.The research is grounded in a case study from primary school classrooms in Shanghai. A lesson entitled “The Colors of Chords and Sketching” was designed within a STEAM framework, combining music, visual arts, and language. Students explored triadic chords by linking harmonic qualities to colors, producing drawings and narratives, and conducting both indoor and outdoor sketching activities. The lesson emphasized embodied and multisensory engagement, enabling students to translate auditory perception into visual and linguistic forms.Findings suggest that cross-curricular music lessons enhance learners’ creativity, engagement, and capacity to transfer understanding across disciplines. Students demonstrated improved ability to connect musical concepts with artistic and linguistic expression, while teachers reported greater collaborative exploration and flexibility in classroom dynamics. At the same time, differences in students’ cultural capital influenced participation levels, revealing challenges in ensuring equity within integrated learning environments. This study argues that STEAM-based models open new perspectives for music education by reframing it as both a bridge between disciplines and a site of holistic learning. By extending beyond traditional subject boundaries, music can foster competencies vital for lifelong learning and social participation. The findings have implications for curriculum design, teacher education, and educational policy, highlighting the potential of cross-curricular strategies to transform music education in school settings.