The school system in Kyrgyzstan includes primary (grades 1 to 4, some schools have optional 0 grade), secondary (grades 5 to 9) and high (grades 10 to 11) divisions within one school. Children are usually accepted to primary schools at the age of 6 or 7. It is required that every child finishes 9 grades of school and receives a certificate of completion. Grades 10–11 are optional, but it is necessary to complete them to graduate and receive a state-accredited school diploma. To graduate, a student must complete the 11-year school course and pass 4 mandatory state exams in writing, maths, history and a foreign language.