Grantham and eminent past students. Britain's first female Prime Minister, Margaret Thatcher, attended Kesteven and Grantham, and Isaac Newton famously attended The King's. Both have remained single-sex up to the age of 16. In 1970, Kesteven County Council (based in Sleaford) announced plans to turn the grammar schools into co-educational comprehensives for ages of 11–16 and leave Grantham College the only sixth form for the town. Later it was proposed to create two sixth-form colleges from one of the grammar schools. Other parts of Kesteven became comprehensive but responsibility for education passed to Lincolnshire under the local government reorganization of 1974,
Isaac Newton author of the manuscript "De analysi per aequationes numero terminorum infinitas", sent by Isaac Barrow to John Collins in June 1669, was identified by Barrow in a letter sent to Collins in August of that year as "[...] of an extraordinary genius and proficiency in these things." Newton later became involved in a dispute with Leibniz over priority in the development of calculus (the Leibniz–Newton calculus controversy). Most modern historians believe that Newton and Leibniz developed calculus independently, although with very different mathematical notations. Occasionally it has been suggested that Newton published almost nothing about it until 1693, and did