Programming is increasingly becoming a subject across the spectrum of educational environments for preschool children. Concerns have been raised regarding a too instrumental and uncritical implementation of programming. This study follows a preschool and reports on the obstacles infused during a six-month design-based study introducing a programmable floor robot with children, featuring formative focus group sessions and pedagogical development. An activity theoretical approach was taken to examine the various tensions with existing pedagogies that arose during the project and how these led to pedagogical development toward a programming ethos based on making pedagogical materials and tinkering activities, where failure is an inherent part of the educational process. The paper discusses the potential problems of using new subjects with current curricula and how new technologies are part of reshaping childhood pedagogies.