Early literacy is often over-simplified as a set of skills for beginning reading, an approach which overlooks the ways that children play their way into cultures, using play as a literacy that accesses popular media as rich literary repertoires of characters and storylines. This article examines how children's play reveals their participatory literacies in preschool classrooms where teachers provide play-based media literacy curricula. Participatory literacies are ways of interpreting, making, sharing and belonging in increasingly globally and digitally mediated cultures. Data are excerpted from a five-year study of literacy play in classrooms that provide a space for children to draw upon popular media repertoires as cultural capital and resources for literacy development. Mediated discourse analysis of classroom video located and analyzed children's play for use of creative and collaborative dimensions of participatory literacies. Results showed that young children drew on their media knowledge during play to fluidly improvise dialogue and story action in ways that enriched and sustained play themes and friendships over time but also allowed isolated children to gain access to play groups. (author abstract)