In recent times there has been an enormous interest in Vygotsky's writing on conceptual development, particularly his insights on the differences between everyday and scientific thinking. In drawing upon cultural-historical theory, this paper seeks to examine the relations between everyday concepts and scientific concepts within playful contexts, such as preschools, with a view to better understanding how very young children develop conceptual understandings in science. This paper presents an overview of a study which sought to map the transformation and appropriation of scientific concepts within two early childhood settings. Approximately ten weeks of data gathering took place, with video recordings, field notes, photographic documentation, and child and teacher interviews for recording child concept formation within these naturalistic settings. The findings indicate that when teacher programs are more oriented towards concepts rather than materials, children's play is focused on conceptual connections. Importantly, the study showed that: It was possible to map the multiple and dynamic levels or stratas of thinking that a child or group of children may exhibit within play-based contexts; An analysis of "unorganised heaps" and "complexive thinking" evident in conceptually or materially oriented play-based programs can be determined; the dialectical relations between everyday concepts and scientific concepts in play-based programs can be understood; and greater understanding about the nature of concept formation in situated playful contexts have been possible.