There are many approaches that support studies of learning in relation to the physical environment, people's interaction with one another, or people's movement. However, what these approaches achieve in granularity of description, they tend to lose in synthesis and integration, and to date, there are not effective methods and concepts to study learning in relation to all of these dimensions simultaneously. This paper outlines our development and use of a new approach to describing, representing, and interpreting people's interaction as they move within and across physical environments. We call this approach interaction geography. It provides a more integrative and multi-scalar way to characterize people's interaction and movement in relation to the physical environment and is particularly relevant to learning research and professional design practice in informal learning settings. The first part of this paper illustrates our development and use of interaction geography to study visitor engagement in a cultural heritage museum. In particular, we illustrate "Mondrian Transcription," a method to map people's movement and conversation over space and time, and the "Interaction Geography Slicer" ("IGS"), a dynamic visualization tool that supports new forms of interaction and multi-modal analysis. The second part of the paper describes one team of museum educators, curators, archivists, and exhibit designers using a computer-supported collaborative learning (CSCL) environment based on interaction geography. We show how this environment used interaction geography to disrupt the conventional views of visitor engagement and learning that museum professionals hold and then reframe these disruptions to enable museum professionals to perceive visitor engagement and learning in innovative ways that potentially support their future design decisions. We conclude the paper by discussing how this work may serve as a blueprint to guide future efforts to expand interaction geography in ways that explore new collaborations across the fields of education, information visualization, architecture, and the arts.