As ecological crises intensify and planetary boundaries are exceeded, early childhood environmental education requires reimagining. Dominant stewardship and child-centred approaches often position children as autonomous actors engaging with a passive environment, reproducing human–nature divisions and obscuring more-than-human agencies. This paper introduces dust pedagogies, a posthuman approach that foregrounds dust and other microworlds as sites of ecological inquiry and relational learning. Drawing on posthuman theory, environmental humanities and Barad’s (2007) concept of intra-action, the study examines children’s encounters with dust through microscopy, multisensory exploration and co-mapping in a kindergarten in Melbourne, Australia. Commonly dismissed as waste, dust is reconfigured as agentic matter entangled with infrastructures, histories and planetary processes. The analysis demonstrates how these encounters connect local, embodied experiences with broader ecological systems, fostering curiosity, care and ethical attentiveness. Dust pedagogies offer a generative pathway for linking early childhood education with environmental justice and planetary boundaries in the Anthropocene.