In practice, some schools have both Protestant and Catholic pupils, but most Catholics attend Catholic schools and most Protestant children attend state controlled schools. In many areas, segregated housing has been important in deciding who goes to which school.
Compulsory education begins at the age of four, as opposed to five in England, Wales and Scotland.
Primary schools take pupils until the age of 11, and there is a selective secondary system of grammar schools and secondary modern schools. It allocates resources for education and controls the supply, training and pensions of teachers. There are 21,000 teachers and 353,000 pupils in schools. Local government has no direct role in administering the annual budget of 1.4bn. The only local political influence on the system is through councillors appointed as members of the Education and Library Boards.