This study investigates the evolving implementation of a praxis-based language assessment initiative as manifested in a number of school cultures. Drawing on Vygotsky’s notion of praxis, wherein theory and practice are tied together and mutually substantiated, this research set out to probe assessment literacy development and practice among teachers in five schools in the periphery of Israel, following the delivery of a teacher in-service course on assessment literacy that was facilitated by one of the researchers. The study examined how and to what extent the knowledge and practice gained in the course were integrated into the schools’ assessment culture. The sample included both coordinators of secondary school language departments and school administrators. The data set is comprised of interviews with participants probing changes in the school setting, specifically with regard to assessment knowledge, decisions, and practices, that may be attributed to the in-service course. A link was established between the schools’ overall profile (characterized here as either conservative or innovative) and the extent of integration of course-acquired assessment culture. The study makes a case for differential assessment cultures and their match with local school cultures.