Children aged six by 15 September must be enrolled in their first school year in that calendar year. In addition, children who reach the age of six between 16 September and 31 December may be authorized to attend the first stage of education, provided a request is submitted by their parents or guardians to the school nearest to their residence (or place of work) during the annual enrollment period. State-run schools are free of charge; private school tuition is refunded by the State in part or fully, when state-run schools in the area are filled to capacity. The first cycle of basic mandatory education covers years 1st-4th, the second cycle years 5th-6th and the third cycle years 7th-9th. The curriculum contains only general education until the 9th year at which point vocational subjects are introduced.