John Dewey's notion of the school as a "social laboratory" influenced educational policy a century ago when the United States underwent a "great transformation" in its educational history toward mass schooling, resulting partly from the "high school movement", where the focus was on "schooling for life". Project-based learning, which builds on Dewey's work on experiential, hands-on, student-directed learning, is ultimately delivered within a student-teacher relationship, and the structure of this relationship and that of the school itself were shaped by an industrial culture that developed during a period of rapid industrialization when the dual revolutions of technology and information processing were transforming the country. During the earlier transition from craft to mass production, schools provided a social context for the task of renegotiating and reframing occupational techniques and world orientations in light of dramatic technological changes. So, too, have the challenges of the current technological revolution shifted the emphasis of education toward students actively using what they know to explore, negotiate, interpret, and create. As a potentially "disruptive innovation" to the traditional schooling model, project-based learning challenges students by acknowledging their roles as participants engaged in producing knowledge. Students also perceive the value of project-based learning, experience this form of learning, and are rewarded through the responses of others to their projects within a community of practice.