This dissertation hypothesizes that school feeder patterns are a hidden mechanism of pervasive inequalities in four-year college completion rates for marginalized students including students of color, students with disabilities, and students from higher poverty neighborhoods. Specifically, this dissertation examines the relationship between elementary to high school feeder patterns and college enrollment on the four-year college completion rates of 8th graders in Chicago Public Schools. To do so, this dissertation seeks to identify the role that elementary to high school to college feeder patterns play in shaping inequities in college graduation for marginalized students and whether elementary school type predicts later college outcomes. This dissertation also examines high school graduation, four-year college enrollment and four-year college completion for male students, who increasingly, are less likely than their female counterparts to complete a 4-year college degree. The overall sample for this dissertation includes all Chicago Public Schools (CPS) eighth-graders (n=156,292) enrolled in CPS between 2004 and 2010, including students who are sometimes omitted from analysis, such as students attending alternative schools, and students with Individual Education Plans (IEPs). Including all students allows for a closer examination of differences in four-year college completion across a more diverse set of students, not excluded through the use of a more restricted sample. Chapter II provides a macro-level view of the longitudinal college outcomes of all CPS students enrolled in the eighth-grade between the years of 2004 and 2010, including students with disabilities, students attending alternative schools, and students attending charter schools. To do so, descriptive statistics and logistic regression models are used to estimate differences in high school graduation, four-year college enrollment, and four-year college completion by race and ethnicity, gender, disability status, and neighborhood poverty level. Chapter III examines the variation in college completion across elementary schools in the district for academically similar students of differing demographic and disability groups. Chapter III introduces a novel indicator, High School College Completion Indicator, to estimate the extent to which high schools are sending and connecting students to four-year colleges where they are likely to earn a four-year degree. Finally, Chapter IV utilizes multi-level modeling, and regression analysis to estimate the mean, cumulative, school fixed-effects students in a given elementary school experience between 8th grade and college; a novel concept referred to as Postsecondary Pathway. This chapter also examines elementary school type as a predictor of positive or negative Postsecondary Pathway. The three studies that comprise this dissertation use Chicago Public Schools administrative data to examine the relationship between elementary school to college enrollment patterns on students’ four-year college completion rates. This dissertation posits that – given elementary to high school to college enrollment patterns— disparities in postsecondary opportunities for marginalized students and male students—are likely detectable as early as 8th grade (the last year of elementary school in Chicago Public Schools). If such discrepancies exist at such an early point in students’ academic careers, there might also exist a potentially valuable point of intervention to improve the college completion prospects of these students before they ever step foot in a high school.