High schools provide schoolwide and classroom level literacy support across content area classes, especially to students who have been identified as struggling readers. These supports range from scaffolded assignments to push in support to reading intervention classes. The nature and goals of these supports is constrained and enabled by broader forces related to literacy and school organization including the institutional logics of high school literacy support, the resources available for providing such support, and district and school messaging about the purpose of students' literacy learning. This three paper dissertation employs lenses from neo-institutional theory and tools from critical discourse analysis to examine high school literacy support at multiple levels of design and implementation. In the first study, I analyze 34 research papers, practice guides, and websites related to secondary literacy in order to identify and interrogate the institutional logics of high school literacy support. The second and third studies draw on data from a comparative case study of two high schools, in two districts, in one state to examine how district and school literacy goals, educators' framing of students' literacy needs, and relevant organizational factors shape the nature of literacy supports and teachers' instruction within and across classrooms and schools. Evidence from these studies indicates that the level of coupling between district and departmental framing of literacy achievement goals shaped how districts distributed instructional resources, how schools organized to provide literacy support, and how teachers positioned students through their instructional support. When districts and departments focused on students' results on standardized assessments, literacy supports were more likely to emphasize skill building, positioning students as disengaged or unmotivated. In contrast, when districts and departments emphasized students' engagement with complex texts, teachers' literacy supports attended to students' affective responses and positioned students as engaged learners. Findings from these studies illustrate often overlooked ideas and norms that become embedded in literacy support program design and have significant effects on adolescents' literacy learning experiences. Together, these studies provide policymakers, administrators, and teachers insight into the ideological and organizational features to consider as they create, revise, or evaluate this support for high school students. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]