Working theories and learning dispositions are key learning outcomes in the early childhood curriculum in New Zealand. However, while there has been a focus on learning dispositions in recent years, less is known about the development of children’s working theories or the pedagogy to support this. The aim of this study was to explore children’s working theories in action in a number of Playcentre settings. The authors were interested in children’s problem-seeking and -solving, theorising, acting and interactions as they engaged in everyday inquiries and conversations with others. This paper discusses some of the dilemmas for educators, including defining and recognising working theories, and deciding what to respond to, and how to respond. When attention was paid to the subtle nuances of moment-to-moment interactions it provided new insights into pedagogy. The findings have implications for early childhood educators as they seek to develop episodes of sustained shared thinking and support the development of children’s working theories over time.