This chapter explores a range of well-established and widely accepted everyday teaching practices that exclude many pupils, for example, our use of subjects, the focus on the written word, and approaches to mathematical problems. It discusses strategies that are intended to enable access but frequently constrain participation, including differentiation, the use of images, and the simplification of language. Drawing upon theories rooted in uncertainty, it considers how our use of such strategies, and to whom we apply them, speak to issues of support, power, and voice. They are about how we define people, and how we let them come to understand and represent themselves. Yet in the process they constrain teachers’ thinking and possibilities for children and young people.