Ian Phillips expresses some frustration with the way the Numeracy across the Curriculum strand of England’s Key Stage 3 Strategy is sometimes presented. He argues that the acid test of cross-curricular numeracy is the value of mathematical understanding in aiding historical thinking and imagination. He criticises attempts to plant numeracy activities in history lessons for their own sake. Instead, Ian encourages history teachers to think about the potential of mathematics to enrich history. Using the kind of data that some history teachers might judge dry or lacking in human interest, he argues that elementary work on such data can illuminate disturbing, colourful and significant stories or trends. Armed with purposeful historical enquiry questions and some basic calculations, pupils can learn to use numerical data to assess historical significance and to build a sense of period that embraces motivation, attitudes and values in the past.