This study explores the role of competing discourses that shape current practices in U.S. schools and how professional development efforts can support teachers and researchers in finding ways to reinsert more democratic processes into their collaborative work. We examine the case of one research and professional development project with the goal of supporting middle school science and ESOL teachers in fostering more meaningful science learning for all their students but especially their English language learners. Using Gee's notion of big-D discourses and Fairclough's notion of interdiscursivity, we trace how the Discourse of accountability, the Discourse of science teaching, and the Discourse of education research, each constructed by different stakeholders for different purposes, may become interdiscursive and hybridized through interaction over time. Excerpts from interviews and conversations with participants during the various components of our project highlight both the challenges and the possibilities of teachers retaining or regaining agency in their classrooms within and against the structures of the accountability Discourse. At the same time, we explore how our researcher Discourse also became hybridized in order to better work with a system where an undemocratic accountability Discourse continues to be dominant.