Reflective practice is one of the key recommended practices in early childhood (EC) education and has been positively associated with the quality of EC teaching; however, research on reflective practice in preschool teaching is limited. In this study, we examined four preschool teachers' reflections on their science teaching exhibited through a four-session science professional development (PD) experience. In the PD sessions, teachers reflected with a facilitator on video clips of their interactions with children as well as children's interactions with science materials; and were provided additional resources that might enhance their reflection. In addition, we investigated change in teachers' attitudes toward teaching young children science before and after the PD experiences. Findings: On average, teachers showed lower levels of reflections (i.e., Description, Justification). However, teachers provided significantly fewer Descriptions (level 1) and more Critiques (level 3) during the last reflection/PD session compared with the prior three sessions when examined more in depth. The teachers showed somewhat different patterns in their attitudes before and after the PD. Practice: PD and reflection sessions with a combination of resources and video reflections seem to help EC teachers enhance the capacity to deepen their reflections about their teaching practices.