Two fundamental questions about science are relevant for science educators: (a) What is the nature of science? and (b) what aspects of nature of science should be taught and learned? They are fundamental because they pertain to how science gets to be framed as a school subject and determines what aspects of it are worthy of inclusion in school science. This conceptual article re-examines extant notions of nature of science and proposes an expanded version of the Family Resemblance Approach (FRA), originally developed by Irzik and Nola ("International handbook of research in history, philosophy and science teaching." Springer, Dordrecht, pp 999-1021, 2014) in which they view science as a cognitive-epistemic and as an institutional-social system. The conceptual basis of the expanded FRA is described and justified in this article based on a detailed account published elsewhere (Erduran and Dagher in "Reconceptualizing the nature of science for science education: scientific knowledge, practices and other family categories." Springer, Dordrecht, 2014a). The expanded FRA provides a useful framework for organizing science curriculum and instruction and gives rise to generative visual tools that support the implementation of a richer understanding of and about science. The practical implications for this approach have been incorporated into analysis of curriculum policy documents, curriculum implementation resources, textbook analysis and teacher education settings.