This research presents a case study of two teachers' emphasis on students' academic identity as a means of facilitating their science literacy development. These cases support a theoretical position that deconstructs the notion of normative science literacy into its constitutive components: (a) being scientific and (b) appropriating its literate practices. Such a perspective views language as a substantive resource for academic identity construction. As such, we utilize a theoretical metaphor of “contextual shifting” to underscore teachers' central role in facilitating student understanding of literate practices associated with school science. Through a cross-case analysis of two elementary science classrooms, we identified ways that students' academic identities were connected to their affiliation with specific scientific literate practices. Our findings reveal that the teachers in both research classrooms utilized teaching practices designed to afford students opportunities to develop academic identities commensurate with science learning. © 2008 Wiley Periodicals, Inc. Sci Ed92:1015–1041, 2008