In 2007 primary education enrollment was around 93%. Many children under five attend a preschool. Children are required to attend school from the age of six. They attend primary school until they are eleven. They are then promoted to the second level of basic education, where they stay until they are 14 or 15. Public school students usually attend classes in shifts. Some go to school from early in the morning until about 1:30 PM and others attend from the early afternoon until about 6:00 PM. All schoolchildren wear uniforms. Although education is mandatory for children, some poor children do not attend school because they must work to support their families.