The purpose of this design-based experiment is two-fold: to see if classroom pedagogies can be developed to improve student achievement in English literature as well as prepare them for 21st Century literacies. Applying Bereiter and Scardamalia's theory of Knowledge Building to English curricula, this experiment tracked the progress of a sixth grade Language Arts class as they engaged in creating theories of literary interpretation supported by Knowledge Forum, a computer-supported, on-line learning environment. The study revealed several key findings concerning how knowledge-building can support student's attainment of "high literacy" in the reading of literature, including maintaining idea diversity, the importance of tentativeness, the manifestations of conceptual artifacts that foster students' co-creation of literary theories, and students constructive use of digital scaffolds appropriate for progressive, literary discourse. Knowledge building supported by Knowledge Forum demonstrated positive effects on student internalization of high literacy skills of thinking, writing, speaking, and listening to others students as they developed more sophisticated literary understandings. [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.]