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 mind. Upon leaving the House of Commons, Thatcher became the first former Prime Minister to set up a foundation; the British wing of the Margaret Thatcher Foundation was dissolved in 2005 due to financial difficulties. She wrote two volumes of memoirs, "The Downing Street Years" (1993) and "The Path to Power" (1995). In 1991 she and her husband Denis moved to a house in Chester Square, a residential garden square in central London's Belgravia district. Thatcher was hired by the tobacco company Philip Morris as a "geopolitical consultant" in July 1992, for $250,000 per year and an annual contribution of