The National Curriculum, which formed the central part of the Education Reform Act of 1988, was a watershed in the development of education in England and Wales. For the first time, a common curricular entitlement and framework was provided for pupils aged 5 to 16 in maintained schools (it is not compulsory for independent schools). The curriculum set out what schools were required to teach in English, mathematics, science, design and technology, information technology, history, geography, music, art, physical education, a modern language in secondary schools and Welsh in Welsh-speaking schools. (Pupils were also to be taught religious education, although not as part of the National Curriculum.) The content of each subject was divided into four 'key stages' to cater for pupils at different ages:
KS1: 5-7 years (Years 1 and 2) KS2: 7-11 years (Years 3 to 6) KS3: 11-14 years (Years 7 to 9) KS4: 14-16 years (Years 10 and 11). Schools were provided with detailed programmes of study and attainment
targets that defined the expected standards of pupil performance at each key stage and formed the basis for national assessments. Provision was made for some pupils, usually those with special educational needs, to be withdrawn from all or part of the curriculum.