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,
Margaret Thatcher not shared by others in her Cabinet. She resigned as Prime Minister and party leader in November 1990, after Michael Heseltine launched a challenge to her leadership. After retiring from the Commons in 1992, she was given a life peerage as Baroness Thatcher (of Kesteven in the County of Lincolnshire) which entitled her to sit in the House of Lords. In 2013, she died of a stroke in London at the age of 87. Always a controversial figure, she is nonetheless viewed favourably in historical rankings of British prime ministers, and her tenure constituted a realignment towards neoliberal policies in