Today's PK-12 teachers and students navigate an increasingly interconnected and interdependent world. This growing interconnectedness and need to navigate life and work in our globalized world have prompted calls for teacher educators around the world to design changes in coursework that inspire teachers to create learning experiences to foster PK-12 learners' development of global competence. The present study applied action research to address this goal in an asynchronous, online graduate teacher education course. Using a principled framework for teaching for global competence (TfGC) across four domains and Global Thinking Routines as pedagogical tools, participants explored an issue of global significance -- the lived experiences of refugees and immigrants across time and contexts -- to learn about TfGC. The article incorporates rich examples of participants' learning and ideas for application of teaching for global competence in PK-12 classrooms in national and international contexts. Participants' responses to key learning activities suggested that including a specific focus on TfGC can be beneficial for current and future teachers. Findings suggest that a thematic approach to TfGC with opportunities to apply pedagogical strategies that can be used in PK-12 classrooms may be productive for encouraging teacher education students to embrace teaching for global competence.