Emerging posthuman paradigms are beginning to influence approaches to educational research and pedagogy, including the "common worlds" investigations of relations among children and wild animals in early childhood settings. This paper turns to child-animal encounters in a secondary school wetlands project to explore some of the implications of posthumanism for environmental education. It explores how singular encounters with wild animals--a swamp hen, a turtle and an eel--became pivot points for young people's affective and creative engagement with the site and emerging issues of environmental responsibility, sustainability and urban land and water management. Though initially the neighbourhood lagoon in the middle of a new housing development seemed to be a tenuous, degraded and domesticated wetland, the students and their teachers began an inquiry into the deep interconnectedness of the site with natural waterways, the animals that move through them, and themselves. Open-ended interdisciplinary inquiries enabled students to choose a range of modes of response including a rap song about the "rescue" of a swamp hen, a picture book that documented the passage of eels from the Pacific to the urban wetland and a dance about a dead turtle.