The paper explores the current rationale for primary science in England with a focus on how competing perspectives arising from perceptions of educational ideology and policy discourse have helped to shape current practice. The aim will be to provide a conceptual understanding of this by focusing specifically on how policy has influenced practice. In particular it will consider the way in which discourse and policy text have contributed to the emergent rationale for primary science which in many ways reflects conflicting influences, views and policies. Data were collected over a year from a regional survey and from four case-study primary schools. The findings suggest that teachers in primary schools face tensions between promoting both an educational and a political rationale for learning primary science. The paper will conclude by suggesting that the justification for primary science should be based on what we already know about how children learn science as well as helping them to develop an understanding of science and how it influences and is intrinsically linked to the needs of society.