Bulgaria’s literacy rate is 100 percent. Education is free and compulsory for children from the ages of 7 through 16; 99 percent of primary school-aged children are enrolled in school. Students attend primary school for four years, basic (or middle) school for three years, and secondary school for three to five years depending on the course of study. About 30 percent of students continue their education past the secondary level. There are more than 20 institutions of higher learning in Bulgaria, including the University of Sofia.