High Schools in England began to teach computing long before the advent of the personal computer and the graphical user interface made it possible to teach aspects of information technology skills to non-specialists. We demonstrate that early high school computing was highly consistent with academic and professional practice. This consistency was eroded from the mid-1980s when the English school curriculum began to emphasise IT skills at the expense of computer science. We explain this development and argue that it helps to account for the growing difficulty in attracting students to university study in the discipline. Finally, we consider some current developments in the English high school curriculum, and reason that they raise concerns that they worsen prospects for the study of computer science.