Project READI (Reading, Evidence, and Argumentation in Disciplinary Instruction) defines reading for understanding in adolescence as the ability to engage in evidence-based argumentation across multiple texts and supports its learning in three disciplines: history, science, and English literature. Disciplinary literacy involves complex critical analysis processes as well as close attention to text. The research team proposes a model that captures these processes while attending to the psychological and social challenges of adolescence. Central to this model is the necessity of viewing evidence-based argumentation as an activity situated in a sociocultural context. This work will contribute to expanding extant reading comprehension models and produce a set of fully tested Evidence-Based Argument Instruction Modules (E-B AIMS) that exemplify core design principles. Each module will include: (1) exemplar curriculum units built on developmental progressions in each content area (history, science, and literature); (2) formative assessments that document student learning and guide instructional planning integral to the units; (3) SenseMaker, a software tool for supporting evidence-based argumentation in the disciplines; and (4) professional development materials (including videotaped instruction, student work samples, and lesson designs) critical to preparing teachers to support instruction that creates opportunities for students to engage in reading for understanding. Partners include researchers at the University of Illinois at Chicago (UIC), Northern Illinois University (NIU), DePaul University, WestEd, Northwestern University (NU), University of Chicago (UC), University of Pennsylvania (UPenn), American Institute for Research (AIR), and Inquirium LLC. A number of school personnel and organizations are serving as key collaborators for the duration of this work.