Early years science education prioritizes nurturing children’s inborn drive to explore, instead of simply delivering factual knowledge. This paper takes the walnut tree male flower inquiry activity sparked by children’s spontaneous curiosity as a research case. Adopting educational narrative and in depth case analysis methods, it explores how science exploration activities unfold and deepen under child-oriented educational ideas. Research findings show preschoolers build science understanding via a repeated loop: sensory perception, active exploration, evidence checking and internalized comprehension. Teachers act as facilitators and curriculum developers, offering emotional backing, thinking-oriented prompts, curriculum planning and meaning making support throughout the whole activity. Peer groups function as a shared cognitive community, pushing children to voice their thoughts and build knowledge together through social interaction. This case unpacks how deep learning comes about: kids need to combine hands-on real world experiences with abstract ideas within the interactive “outdoor，classroom，outdoor” learning context. It supplies practical references and actionable suggestions for developing emergent science curriculum in kindergarten settings.