Abstract This paper presents an analysis of the literacy practices in a primary-grade English immersion class in California during the first year of implementation of Proposition 227, the initiative that mandated English immersion education for a majority of the state’s linguistically diverse students. The data issue from a yearlong qualitative study of Room 110, a class consisting of 20 native Spanish-speaking children. The author utilizes the notion of hybrid literacy practices to conceptualize the blending of Spanish and English and home and school registers that permeated the class’s reading and writing activities. Findings illustrate the dynamic contexts of development created by these practices and ways that the linguistic hegemony operating within the school eclipsed the practices. A discussion of the findings emphasizes the ambivalence of hybridity as a conceptual tool and as a guide for instructional practice. The paper concludes with three interrelated principles gleaned from the analysis of Roo…