This chapter explores the transformative potential of generative artificial intelligence (GenAI) in science education. Drawing on the theoretical lens of new materialism, it reimagines science education as a co-agential process involving both human and non-human agents. The chapter positions GenAI not merely as a tool, but as a dialogic partner capable of scaffolding inquiry, modelling complexity, and supporting epistemic reflection. It examines how GenAI challenges traditional notions of knowledge, assessment, and authorship, and calls for critical AI literacy that includes ethical awareness, material engagement, and inclusive representation. Emphasizing the need for robust infrastructure, clear policy guidance, and effective professional development, this chapter offers a vision for a science education that is critically engaged and human-centred in an age increasingly shaped by artificial intelligence.