Curriculum history has become a consolidated field of research in Canada and the United Kingdom. This research has helped us better to understand how school knowledge is socially constructed. The curriculum, far from what we usually think, is not a static entity that remains the same over time. As with other aspects of the education system, school curricula are influenced by political, economic, and cultural aspects and by the schools themselves. Questions that can provide an overview of such curriculum history research are: what are the origins of this field of study in Canada and the UK? What kind of research has been carried out so far? How does the curriculum really change? This entry is organised into three sections. The first section outlines the historical origins of this research. It examines the most important studies, how they arose, and also explains some of the early criticism that sparked further development in the field and generated new lines of study. In the second section, the entry explores the current debates on curriculum history in Canada. Some of the most interesting works on the field and new research that has been initiated are presented. In the third section, the UK studies are analysed to show how they have deepened into new, extensive proposals for further study. As can be seen, the curriculum history in Canada and the UK continues to provide a rich field for research that shows how the curriculum is a social phenomenon that still offers interesting study opportunities.