Early science inquiries and experiences increase young children's awareness and interest for science. The importance of promoting science process skills which bolster children's confidence to formulate and communicate personal ideas have been emphasised by international guidelines. As Loose Parts Play (LPP) is a form of free play involving open-ended play materials, its flexible nature promotes active exploration with materials that encourages children's interaction with science-related experiences. This teacher action research aims to explore the influence of open-ended questions on children's science process skills, as well as the scientific concepts that children are capable of exploring independently during play experiences. Analyses draw on video- and audio-recorded observation, child observation notes, and teacher journals. A total of 180 open-ended questions were employed by the teacher-researcher and 155 instances of science process skills were observed in a group of five-year-old children. Findings revealed that periods of uninterrupted play time followed by open-ended questions, extend children's science process skills, and add complexity to their scientific exploration. Furthermore, children were observed to self-initiate exploration of scientific concepts, such as transforming materials and changing motion, during these uninterrupted play periods. Overall, this teacher action research highlights the pivotal role that educators play in young children's playful learning experiences, where their timely use of open-ended questions has the capacity to facilitate children's early science learning during LPP. This study serves to define an educator's role within student-driven or child-initiated learning experiences, as well as guide educators in the utility of loose part materials, provision of uninterrupted play periods, and planning of open-ended questions to stimulate children's science exploration.