This study examined the dimensions of the structure-agency dialectic embedded in students' embodied narratives of their science experiences. As three Black high school students with developed dancer identities used what I have named "ethnodance" to author and narrate their evolving science identity, I looked for structures that hindered or supported their development as well as their agentic choices, resistance, and advocacy. I present an empirical illustration of dimensions of the structure-agency dialectic embedded in students' ethnodances and reflection. Building on the consideration that for students whom a meaningful part of social life includes movement and dance, the theoretical argument frames ethnodance as an embodied narrative, dance as a form of cultural expression and social life for some Black youth, and identities-in-narratives as a window into students' agentic power to disrupt normative science ideologies and carve a place for themselves in science. Furthermore, students' ethnodances conveyed how changes to the science course sequence, physics discourse, and expectations from trusted adults limited or hindered their participation in science, and self-advocacy, choice, and resistance constructed, de-constructed, or re-constructed their competence in science.