This paper has its origins in the EU Comenius funded GeoCapabilities project. From its outset, the project developed and researched the notion of powerful disciplinary knowledge (PDK) as an underlying principle of curriculum making in the context of secondary school geography teaching. The work, led from the UCL Institute of Education and involving school teachers, teacher educators and other stakeholders across eight mainly European jurisdictions, was framed by Young and Muller's 'three educational scenarios' (Young & Muller, European Journal of Education, 45, 2010 and 11). The three futures heuristic is discussed as a means to distinguish qualities of curriculum thought. Future 3 scenarios, which posit teachers as curriculum makers with responsibility to engage in essential 'knowledge work', provide a principled platform on which to develop ambitious educational classroom encounters. Knowledge working with PDK and (as we go on to argue) other powerful ways of knowing the world, is seen as a bridge between social realist epistemological principles and practical classroom content selections. This opens the possibility of responding to Deng's (Journal of Curriculum Studies, 54, 2022) call for developing practical theories of content with teachers. Although the authors are geographers in education drawing on different international perspectives and traditions, the paper addresses matters of interest applicable to a variety of specialist subject domains across the secondary school curriculum.