The national movement to integrate computational thinking (CT) and computer science (CS) into K-12 education has led to rapid expansion. However, this growth is challenged by the reality that many in-service teachers asked to teach CS/CT are novices with little formal preparation. Professional development is critical to bridging this gap, yet many programs struggle to connect with teachers’ diverse experiences and move beyond theory to classroom practice. This paper presents an experience report from a multi-year one-week summer course serving over 100 middle and high school teachers, the majority of whom were novices in CT. Our work contributes a novel “Dual CRP Model” for CT professional development grounded in the principles of Culturally Relevant Pedagogy (CRP). This model is structured around two key components within each session: a “Teachers as Learners” mini-lecture that connects CT concepts to teachers’ own lived experiences, followed immediately by a “Teachers as Teachers” hands-on exercise where they adapt K-12 CT activities for their own students. Pre- and post-course survey data consistently show that teachers enter with low confidence and leave feeling highly prepared to teach CT. Qualitative findings and an analysis of course artifacts reveal that the model’s success stems from its use of culturally relevant analogies to make concepts accessible and its bridge from theory to classroom practice, which are key factors in building both conceptual understanding and pedagogical confidence.