My research uses interaction analysis to investigate two STEM education spaces and discuss how instructors can and should notice and address unproductive group dynamics, particularly in the service of creating more humane learning environments. The primary goal of this work is to investigate how inequities emerge and continue as interactions in STEM spaces unfold. In the first chapter, I describe how my own experiences of marginalization in physics classrooms and my position as a learning assistant led me to pursue physics education research. The second chapter discusses my researcher positionality and how interaction analysis techniques address my research questions and sheds new light into my research areas. The first body chapter focuses on how tutorials may contribute to inequitable group dynamics. Even though we do not traditionally think of tutorial writers as instructors, they can spot harmful groupdynamics emerging in pilot testing of the tutorial and they should modify the tutorial accordingly. In the fourth body chapter, engineering Learning Assistants, undergraduate teaching assistants, address harmful group dynamics emerging in freshman-level engineering design teams. Role-plays in the LA pedagogy seminar make visible some of the harmful ideologies that constrain LAs diagnoses and proposed treatment of teamwork troubles, creating space for the LAs to discuss and challenge those harmful ideologies. I conclude by discussing insights which cut across both research spaces, including how equity is conceptualized and learning environment design.