This paper examines the emergence of schools "micro-computing" in the UK between 1977 and 1984--a period of significant educational, technological and political change. During this time, computing developed rapidly from a niche activity in a few select schools to the state subsidized purchasing of a "computer in every school" and the nationwide promotion of computers as a feature of curriculum and pedagogy. Through a series of in-depth retrospective interviews with key policy actors (n = 20) this paper develops a detailed "policy historiography" of this period--shedding light on the complex power relations and interests that underpinned these developments. In particular, the paper highlights the origins of these policy interventions in earlier activities, and examines the negotiations and conflicts between and within the two government departments involved in the mass introduction of computing into the UK school system.