This symposium presents research that uses video-based ethnographic methods to sample the range of ecological events and contexts in young children's lives and thereby document the what and how of naturally occurring learning and development. All four papers presented focus on the interactional arrangements of social, cultural, and material supports for learning within contexts. The specific focus is on the social functions and social occasioning of practices across settings. The first two papers examine two common interactional arrangements - questioning and imitation - and the qualities of these arrangements across settings. The final two papers examine two common childhood activities in context - building with blocks and watching television - in order to understand how children engage in these activities and how that engagement is mediated by different interactional arrangements across settings. The combined effect of these papers is to begin to map the socio-material arrangements and interactional routines that contribute to young children's everyday learning, a neglected focus in the learning sciences.