Recent literature in science education suggests that, to transform girls' participation, learning, and identities within school science, we must think about ways to engage girls in different kinds of educational activities that promote broader meanings of science and scientist. This study was designed to examine more deeply this call for a changed science curriculum and its implications for girls' participation, interest, and emerging science identities. In this ethnographic study, I examine the culturally produced meanings of science and scientist in a reform-based physics classroom that used a curriculum called Active Physics, how these meanings reproduced and contested larger sociohistorical (and prototypical) meanings of science and scientist, and the ways girls participated within and against these meanings. The girls in this upper middle class school were mostly concerned with accessing and maintaining a good student identity (rather than connecting to science in any meaningful way) and resisted promoted meanings of science and scientist that they perceived as threatening to their good student identities. Their embrace of the ways school defined success (via grades and college admission) produced a meaning of Active Physics as a way to get credentials on a transcript and ensured their disconnection from real-world, meaningful science and science identities. The story of girls' participation and resistance in Active Physics complicates our quest for gender-fair science and highlights the power of sociohistorical meanings of schooling and science in producing educational subjects. Ă