Background/Context: Financial aid is a critical policy lever for increasing college access, choice, and attainment. Even with the substantial investment in financial aid programs, however, inadequate financial resources continue to limit postsecondary educational attainment. The persistence of financial barriers despite the substantial annual investment in student financial aid programs suggests the need to better understand the role of financial aid in promoting college opportunity. Purpose: The study explores three questions: What are high school students' perceptions of and expectations for financial aid? How do these perceptions and expectations inform college-related behaviors? How are perceptions and expectations for financial aid influenced by the state and school contexts in which students are embedded? Research Design: The study uses data from descriptive case studies of 15 high schools, three in each of five states: California, Florida, Georgia, Maryland, and Pennsylvania. Within each state, we purposively selected three high schools. The three high schools, selected from one school district or metropolitan region, may be characterized as relatively "low," "middle," or "high" resource based on the demographic and academic characteristics of enrolled students. Conclusions/Recommendations: The results of this study suggest the importance of considering perceptions and expectations about aid, rather than actual amounts of available aid, when examining the relationship between financial aid and students' college-related decisions. The results also suggest that knowledge and understanding of aid are related to characteristics of the schools that students attend and characteristics of available aid (an aspect of the state context). In addition, the results indicate that perceptions of and expectations about aid may encourage students to engage in other behaviors that promote college access and success, particularly academic preparation. The article concludes by offering implications for future research.