The role of schools and physical education in promoting health, producing a "healthy nation" and in tackling obesity has been increasingly recognised in recent years. In England this is evidenced by various policies, strategies and responses from government that have highlighted schools to be instrumental in addressing health broadly and obesity specifically. In addition, individual schools and teachers at the local level appear to be responding to the obesity issue in varied and different ways. However, we and other researchers feel that the discourse surrounding obesity and some of the reports, messages, policies and measures being taken to tackle it are misleading, misguided and could do more harm than good. At the same time, as physical educators committed to the health and development of young people, we feel unable to ignore the issue and compelled to act. We contend that "every child of every size matters" and can benefit from regular engagement in physical education and physical activity and furthermore that, as a profession, we have a responsibility to provide all young people, of all sizes, with meaningful, relevant and positive physical education and physical activity experiences. Given this, we consider what role physical education can and should realistically, sensibly and safely play in addressing childhood overweight and obesity. Firstly, some of the key "facts", issues and debates concerning obesity are explored and the way in which the issue appears to be being addressed in many schools is critiqued. We then briefly summarise some of the formal guidance and recommendations available to schools on obesity, before concluding with some practical recommendations to support physical education teachers in effectively engaging all children in physical activity both within and beyond physical education. (Contains 3 tables.)