This chapter will chart and discuss research into the real-life world of physical education in schools. What goes on in the gymnasium, or on the sports field or in the sports hall? I hope to indicate clearly what we currently know about teaching and about what the teaching and, crucially, the learning, of physical education achieves for the pupils who experience the school subject. There has been a series of easily identifiable phases in classroom research not only into physical education, but also into teaching in general, and these will be discussed, and instances of ‘landmark’ studies described, to obtain as full a picture as possible about what really happens in school physical education. Although much of the research referred to has been conducted in the United States, I have included studies from elsewhere, particularly Britain, where appropriate and relevant.