Efforts to understand disparities in educational outcomes between students designated as English Learners (ELs) and their monolingual English-speaking peers have focused on factors that limit ELs' access to college, including quality of high school preparation. Central to quality high school preparation are schools' curricular structures--the course sequences and programs through which schools deliver curriculum and instruction. This article presents findings from a study of curricular structures at three comprehensive high schools, examining factors that influenced school leaders in the design of structures. The study found that, while principals articulated sociocultural views of language learning that emphasized ELs' integration and engagement with English-speaking peers in rigorous content learning, the schools' curricular structures limited ELs' access to such opportunities. Two key themes emerged that help to explain the misalignment between the principals' beliefs and the structures they put in place: conflicting goals for their students and concerns with teacher staffing.