The public school system is managed by the Chennai Corporation with an enrollment of 142,387 students in over 330 schools.[404] Tamil and English are the primary medium of instruction, though some schools also use Telugu and Urdu as medium of instruction in their schools.[404] Public schools run by the Chennai Corporation are all affiliated with the Tamil Nadu State Board, while private schools may be affiliated with either of the Tamil Nadu Board of Secondary Education or the Central Board of Secondary Education (CBSE).[405] A few schools are affiliated with the Council for the Indian School Certificate Examinations,[406] the National Institute of Open Schooling (NIOS) board or the Montessori system.