The goal of this study is to investigate the role of English Language Arts (ELA) teachers' verbal discourse moves in scaffolding adolescent students' argumentative thinking in small group interpretive discussions about literature. Demands related to argumentation may present particular challenges for adolescent students (Biancarosa & Snow, 2004; Nippold, Hesketh, Duthie et al., 2005; Voss & Means, 1996). Consistent with the sociocognitive perspective on teaching and learning, instructional approaches that involve enhancing the quality of classroom discussion are considered to be one fruitful approach to fostering students' argumentative skills (e.g., Goldenberg, 1992; Soter, Wilkinson, Murphy, 2008). This dissertation employed a mixed-methods design and analysis that proceeded in several phases. First, I employed sequential analysis to characterize students' responsiveness to ELA teachers' prompts for particular argumentation strategies during a series of 10 literary discussions. Second, I used bidirectional analysis in order to characterize the individual discussions in terms of the magnitude of interdependence between teacher prompts and student argumentation strategy use, and to observe the ways in which this interdependence evolved over the series of discussions. Third, findings from this statistical investigation then provided the basis for selecting segments of discussion that illustrated the ways in which this verbal scaffolding was enacted. Finally, I examined how adolescents used evidence in these literary discussions, and the extent to which the various types of evidence students' used reflected teachers' conceptions of ELA disciplinary conventions. Results showed that teachers enacted their own specific patterns of verbal scaffolding. Patterns of argumentation strategy prompts and responses were not homogeneous across classrooms, and the interdependence of these talk moves evolved over time, depending upon the teachers' perception of student performance. Students were most responsive to teachers' prompting for evidence, followed by claims, and then reasons. Of the four different types of evidence identified in the data, students most frequently employed analogical reasoning to support interpretive arguments, which did not align with teachers' disciplinary focus on textual evidence use. Findings add to our understanding of argumentation from the perspective of adolescent development and disciplinary literacies. [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.]