Modern open school architecture abstractly expresses ideas about choice, flexibility and autonomy. While open spaces express and authorise different teaching practice, these versions of school and classrooms present challenges to teaching routines and practice. This paper examines how teachers adapt as they move into new school buildings designed and built on the concept of openness. After considering how modern architectural and education concepts of openness authorise different approaches to teaching and learning, a case study is provided of how teachers perceive and respond to these action possibilities. The main conclusions are that the nature of open schools and classrooms means that it is difficult to achieve a mature system with coherent pedagogical practice, a shared culture and mutuality between teacher and student learning. Rather, there is a continual process of negotiation as teachers react and adapt to the affordances of open learning environments. Hybrid pedagogy tends to result from the friction between routine and possible practice within open space, increasing the intensity of teaching practice.