The purpose of the study was to investigate prospective early childhood teachers' conceptions of teaching science, and thus identify their strategies for enabling their future pre-K to 3rd grade students' construction of science content. For the purpose of this study, we subscribed to the view of conceptions of teaching as having dimensions and orientations reflecting two different models of learning, active learning and passive learning respectively. One hundred prospective early childhood teachers' drawings and narratives of teaching science in early childhood classrooms were thematically analyzed to identify their conceptions of teaching science. Forty-six participants conceptualized demonstrations and teacher explanations as instructional strategies and as sources of science content knowledge to transmit defined bodies of science content knowledge to their students (passive learning). Fifty-four participants conceptualized experiments as student-based active learning environments that permitted students to think, discover, collaborate and construct their own science content knowledge and/or co-construct science content knowledge with teachers (active learning). The findings of the study provide a framework for focusing on how prospective early childhood teachers conceptualize science instruction for children in pre-K to 3rd grade classrooms and their strategies for helping their future early childhood learners in constructing science content. The study also calls for early childhood teacher education curricula to incorporate frameworks for understanding the practice of teaching within coursework early on in the early childhood teacher preparation program to enable prospective teachers to reflect on and document their prior knowledge of science instruction.