The UK Education Act 1944 made numerous major changes in the provision and governance of secondary schools in England and Wales. It is also known as the "Butler Act" after the Conservative politician R. A. Butler, who wrote the legislation after consultation with all parties. Historians consider it a "triumph for progressive reform," and it became a core element of the Post-war consensus supported by all major parties.

Butler designed the Act as an expression of "One Nation Conservatism" in the tradition of Disraeli, which called for paternalism by the upper class towards the working class.

The Act sharply distinguished between primary and secondary education at age 11 and ended the traditional all-age (5-14) elementary sector, enforcing the division between primary (5–11 years old) and secondary (11–15 years old) education that many local authorities had already introduced. It abolished fees on parents for state secondary schools. It brought a more equitable funding system to localities and to different school sectors. The Act renamed the Board of Education as the Ministry of Education, giving it greater powers and a bigger budget. While defining the school leaving age as 15, it granted the government the power to raise the age to 16 "as soon as the Minister is satisfied that it has become practicable", though the change was not implemented until 1973. It also brought in a new system for setting teacher salaries.

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