The authors of this study are teacher-researchers, the first is a university researcher and former third and fourth grade teacher, while the second author is a universitybased science educator. They report findings from a community-based study that Ralph, the first author, and his students conducted across two academic years (2001)(2002)(2003) in order to illustrate the ways in which the next generation science standards and learning progressions can be appropriated as social-constructed practices inside and outside of school. The authors argue that what constitutes science learning in school is not a 'state of grace' dictated by standards. Rather, becoming a scientist within a community of learners is a cultural phenomenon that teachers and students co-construct and as such teachers can approach the next generation science standards and learning progressions as opportunities to create intentional, disciplinary practice-based learning communities inside and outside of school.The language and vision of next generation science standards (NGSS), along with their learning progressions and cross-cutting concepts, provide new opportunities for conceptualizing how we approach science learning in K-12 settings. These standards develop students' development of disciplinary knowledge by having them acquire practices, discourses, and in developing habits of mind like those of adult members of those disciplines. This aspect