Objective: This study reviews the status of materials in curriculum and reform, as reflected in a network case study of curriculum in one kindergarten classroom in the United States. This paper focuses on the events leading up to and building upon one inquiry unit that became a focal point in promoting progressive curriculum reform at the school. Method: Methods from Actor Network Theory are employed to attend to a wide cast of human and nonhuman actors, trace their mobilities, and map them into curricular networks. Data, collected over 9 months of one school year, included field notes, audio recordings of conversations, and images of classroom objects and arrangements. Results: Three material assemblages--a closet, a bulletin board, and a curriculum timeline--are viewed as agents assisting in stabilizing the inquiry unit and sustaining further student-centred inquiries amidst competing curricular reforms and policies. Findings demonstrate how teachers may mobilize such assemblages to accomplish multiple objectives, as is necessary when navigating tensions from multiple parties or reform mandates. Conclusion: This study contributes to scholarship conceptualizing the status of curriculum materials, with particular attention to their functionality at the nexus of both the micro-interactions of curriculum enactment and the macro-politics of educational reform.