In western democracies like Canada, children develop understandings of themselves by participating in physical, social, and civic activities. Such activities occur in the built environments within which they live, learn, and play. Children with motor impairments are only able to engage in these activities in environments that are accessible. These children comprise a small, marginalized population that has rarely been included as research participants. Hence, very little is known about their perspectives of the accessibility of their environments. To redress this knowledge gap, we conducted an exploratory sequential mixed methods study with and for physically disabled children to garner research evidence that could be used to optimize Canadian public policies. Using child- and disability-friendly methods, we aimed to determine: 1) the accessibility of homes, schools, and neighborhoods; and 2) how disabled children navigated and evaluated these environments. To these ends, we conducted an ethnographic Case Study Series (n=13), which yielded intensive research findings. Using the key ethnographic findings, we developed a cross sectional survey for a larger sample of children and youth (n=428). This article describes the strategies used and challenges faced to design and conduct this research.