In this paper, we describe the work of a teacher (Sarah) as she attempted to use culturally relevant pedagogy in her physics classroom. Culturally relevant pedagogy (CRP) is an approach to teaching developed by Gloria Ladson-Billings, with the goal of encouraging learning through drawing on students' cultural capital as a centerpiece of their instruction. CRP meets the academic and cultural needs of diverse students through recognizing and building upon their cultural backgrounds, experiences, and interests in instruction. We describe how our experience working with Sarah broadened and honed our original understanding of CRP as we documented Sarah's instructional successes, as well as the challenges, she encountered in her physics teaching. Based on our work with Sarah, we provide recommendations to inform other physics teachers as they attempt to employ CRP.