My dissertation explores the higher education transition decisions made by senior high school students from diverse social backgrounds in Chile. I examine how family, school, and the broader institutional and political context interact with and influence these decisions during times of major social changes and educational reform. Through a 10-month qualitative multi-site case study, I interviewed senior high school students from different social backgrounds and schools, and their close social networks. Building upon the concept of "college-going habitus," I examine how family support and expectations shape students' higher education choices. My findings suggest that all students participating in my study exhibited clear predispositions towards pursuing higher education, being endowed with a certain kind of "college-going habitus" transmitted by their families and mediated by social class. Yet, I find that this college-going "habitus" is a more nuanced phenomenon than has previously been acknowledged. By proposing "acquired" and "incipient" forms of "college-going habitus" among lower-class students, besides the traditional "inherited" one exhibited by the upper-class, I argue that "college-going habitus"--even though largely dependent on social class--can also be developed through discourses willfully integrated and learned over time, mainly through the strength and nature of explicit parental discourses and encouragement. My study also finds that the relationship between schools and its students' college accomplishments is more complicated than simply "reproduction" or "school effect." A school's socioeconomic status influences certain resources, organizational practices, and teachers' expectations, but does not preclude schools from diverging and making a difference--for better or worse--in their students' college decisions. My findings posit that a school's academic rigor, quality of the standards in the education imparted, and the implementation or lack of robust college-readiness strategies, largely determines whether a school exerts a positive effect, a no-effect (reproduction), or a negative school effect on students' aspirations and college decisions. Finally, my dissertation shows that not only educational policies and reform influence students' views on college opportunities and choices, but unexpected social events, such as the October 2019 Social Outburst in Chile, also have dramatic consequences on students' perceptions of the opportunities available in Chile and, in turn, on their own college aspirations and decision-making. My research illuminates how the social outburst triggered a shift in students' discourses about opportunities, from an emphasis on a meritocratic approach to a focus on prevailing inequalities. This gives rise to a revised meritocratic discourse that puts the accent on effort rather than on merit (i.e., actual performance), placing an even greater burden on lower-class students. In sum, my research sheds light on the complex interplay of factors influencing Chilean high school students' higher education choices, offering insights into the nuanced nature of the college-going "habitus," school effects, and the impact of societal events on students' aspirations and decisions. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]