We present an overview of an inquiry approach to developing tools to support inquiry-based teaching and learning. Our approach sees inquiry as involving transformation of situations not simply learning concepts, engaging people in multiple forms of collaboration, and envisioning tools as both the means and products of inquiry. To illustrate these ideas we tell the story of the Inquiry Unit, a web-based means for people to describe processes of inquiry. Over the last eight years the Inquiry Units have evolved from a simple mechanism for teachers to share curriculum units with other teachers into a general mechanism for people in community centers, libraries, school, and other settings, to engage in collaborative inquiry. These changes have included mechanisms for co-authorship, comments, spin-offs, document sharing, and group and community support. Central to our discussion is how these features emerged through an open, participatory process of reflective inquiry.