In a global and volatile world, teachers are being constantly challenged to support students' literacy development and assist them to develop knowledge and skills to expand into new ways of knowing. This two-year school-university partnership is dedicated to enhancing teachers' learning about language with the goal of building teachers' repertoires in ways that promote effective literacy teaching within their subject specific teaching areas in an Australian high school. The project is grounded in theories of knowledge structures of discipline learning within the sociology of education and associated social semiotic theories of language as a resource for meaning making. The project utilizes formative experimental methodology to understand how teachers enact text-based approaches to school-based literacy. Initial findings reveal how a partnership based on trust, mutuality, and reciprocity motivated teachers to make small but measurable changes to their classroom practice in one area of literacy development.