How much curriculum change is appropriate? Defining a zone of feasible innovation

The article grapples with the question of how much curriculum change is appropriate in a given context and in a given time frame. How can a balance be struck between stagnation, on the one hand, and the promotion of unrealistic innovation on the other? In answer to this dilemma, the concept of a zone of feasible innovation (ZFI) is proposed and explored, drawing on the literature of school development, teacher professional development, and of developmental psychology, the work of Vygotsky in particular. A series of procedures are suggested to help define the nature and scope of a ZFI in any given situation. Finally, vignettes from case studies of innovation in science education are evoked to provide real‐life counterpoints to the theoretical constructs of the literature.