We report on the use of bilingual constructed response science assessments in the context of a research and development partnership with secondary school science teachers. Our project provided a series of workshops for teachers where they explored students' emergent reform-oriented science meaning-making in our project-designed assessments. We used discourse analysis to explore how three different groups grappled with the relationship between science and language in this context: (1) researchers' emergent understandings of how to create improved resources for teachers to better integrate science and language; (2) students' emergent understandings as expressed in their assessment responses; and (3) teachers' emergent understandings of how to integrate science and language in their instruction as expressed in interviews in the teacher writing workshops.