Literacy should be viewed as the ability to enlist a repertoire of discourse forms to explore and extend thinking and learning. In this view of literacy and literacy learning, various forms of reading and writing are seen as distinct ways of knowing and acquiring knowledge for ones' own purposes. Supporting this view of literacy are theoretical and research findings from various sources, including research in reading and writing, knowledge acquisition, and current functional approaches to literacy. However, while studies have examined the influence of a restricted array of teacher-initiated reading and writing tasks on content learning, researchers need to investigate in-process thinking and learning by individuals involved in the self-directed use of reading and writing activities. In terms of instruction, the development of literacy repertoires is a major goal as students study difficult topics and attempt to solve complex problems. Helping students acquire a "critical literacy"--the ability to use reading and writing for purposes which exceed those most often associated with minimum competence--is of utmost importance, and may warrant a reconceptualization of literacy learning that would entail a critical analysis of current principles and practices dominating how reading and writing are used and taught across the grades. (Fifty-four references are appended.) (MM)