The Greek education system has three main levels: compulsory education from ages 4-15 including pre-primary, primary, and lower secondary; post-compulsory education from ages 16-18 including upper secondary schools and vocational schools; and post-secondary and tertiary education for ages 18+. The system is overseen by the Ministry of Education and administered regionally through 13 Directorates of Education. The Directorate of South Aegean Sea oversees 596 schools and 7072 teachers across the Cyclades and Dodecanese islands.