A school in an educational system operated, supported, or administered by the state; specifically an elementary school in England or Wales operated by the National Society for the Education of the Poor, established in 1811 (now historical); (in Ireland) an elementary or primary school of a type established after 1831 under the National System of Education.
The number of national schools declined in England and Wales after the 1870 Education Act, which provided free education to the children of the poor.
national school/ˌnaʃ(ə)n(ə)l ˈskuːl/ /ˌnaʃən(ə)l ˈskuːl/
Early 19th century; earliest use found in untitled. From national + school.