Growing a diverse STEM workforce requires that we train and recruit teachers of color into the STEM teaching field as role models and agents of change for our increasingly diverse student population in the United States. Using the overlapping frameworks of racial and science teacher identity development, I studied participant experiences and beliefs in a 15-week, science teaching practicum course for future science educators. Specifically, I examined shifts in identity in 20 prospective K-12 teachers with a focus on seven students who identified as Black, Indigenous and People of Color (BIPOC). The purpose of this study was to create an ethnographic account of how concepts of identity, biases, and linguistic diversity in science can be understood and addressed by undergraduate instructors in this context. Data was collected via in-depth interviews, reflections, lesson plans, and lesson observations and analyzed using a qualitative content analysis method.Findings indicated BIPOC students' identities as science teachers changed throughout the practicum course, from a sense of exclusion and difficulty, to a sense of success and belonging in teaching. Additionally, it was found that these future K-12 teachers developed more positive attitudes and explicit strategies toward the implementation of equity focused, linguistically diverse, inquiry-based science teaching, as a result of the course. Because science identity development is influential to learning and teaching, the results have significant implications for the design of teacher education programs and support of K-12 teachers in teaching science. Results indicated including early preparation in science teaching through the form of practicum-based learning can be beneficial in BIPOC science teacher preparation and identity development. v Acknowledgements I wish to thank my committee members Dr. Stephanie Sisk-Hilton, Dr. Lawrence Horvath and Dr. Maricel G. Santos for their guidance and support. They have been allies, mentors and critical colleagues as I navigated this academic journey. I continue my scholarship to honor the legacy of these amazing teacher educators. They bring joy and passion to the work they do every day and I aspire to do the same. I also want thank my best friend and husband Blas Craig Herrera, who is a fellow science educator. I do this work for him and our BIPOC colleagues. Transformative education happens when our fellow people of color are at the head of these classrooms, changing science and identity for our future generations. I wish to acknowledge my parents Peter and Anna Chan, and my daughters Kira and Cassidy Herrera for all their love and understanding. I work to honor their legacy, past and future. The collective love and support of these people and the greater community at SFSU made this possible. Lastly, I thank the thousands of past students who give me strength to fight for justice and equity in our classrooms and the motivation to continue to share our stories with the world. viTable of Contents Certification of Approval .