How can teachers enact a curriculum that is responsive to students and emergent from them when teachers are under enormous constraints to cover specific course content and to prepare students for standardized tests? Rather than an either/or perspective, this article embraces a both/and approach based on the belief that teachers can do both. Drawing upon qualitative classroom data gleaned from 3 years of research in an inner-city high school, four "best practices" inform a science curriculum model based on student voice and choice. In a recursive fashion, both the evidence and aspects of the curriculum that instantiate these practices are described. The end result is a new way of thinking about high school curricula that is situated in the students' lives and experiences and has room for their voices and choices while addressing content standards and the development of critical thinking skills. It also demonstrates how research can inform curriculum development in overt and significant ways, when empirically identified best practices are made visible in a curriculum's organization and implementation. (Contains 3 tables and 9 notes.)