In the context of a study investigating a teacher learning program, DIA, designed to encourage practices of mediation and promote teacher well-being and holistic learning for students, we evaluated changes in teachers' practices and perspectives following training in the DIA program. We used qualitative measures, including focus groups, writing samples, drawing samples, classroom observations, and lesson plans and workbooks. Our analysis found that teachers who participated in DIA expanded their identity as a teacher, conceptualizing their role as mediators of learning. The DIA training provided ideational, material, and relational resources that supported this expansion of teachers' identities, allowing them to access new learning and implement new practices of holistic instruction.