Secondary education in Denmark
Secondary education in Denmark (in Danish: ungdomsuddannelse, "youth education") usually takes two to four years and is attended by students between the ages of 15 and 19, after finishing primary education by 9th or 10th grade. Secondary education is not compulsory, but usually free of charge, and students have a wide range of programmes to choose from.
Source: Wikipedia — Secondary education in Denmark (CC BY-SA 4.0)