Schools in England and Wales since the late 1980s have been compared in terms of their performances in public examinations and standardised test scores in the form of "school league tables", with Wales ceasing to produce these after 2001. One of the factors related to performance in examinations is the choice of the examination board, with five main boards currently active in England and Wales. In this paper, we study differences in student uptake and performance among boards and how this has changed over time. By contrasting the experiences of England and Wales the results of our analyses provide a commentary on recent attempts to understand the effects of league tables on school performance.