Despite constitutional provision that places responsibility for education in the hands of states, provisions in each Australian jurisdiction are similar. Education is provided as: preschool education, school education, and tertiary education (consisting of vocational education and training), as well as higher education. Preschool education is provided through a variety of arrangements for a majority of 3- and 4-year-olds. Formal schooling is provided for 12 or 13 years and attendance is compulsory between ages 6 and 15. Non-government schools provide for 30 percent of school students. Sets of similar curriculum frameworks, often based around eight key learning areas, are used as the basis for teaching in most states. As a result of expanded educational participation over the last two decades of the twentieth century, at least 70 percent of students complete a full secondary education and nearly four out of ten attend a university, by the age of 19 years. A comprehensive system of vocational education and training that includes apprenticeships provides (typically on a part-time basis) for nearly 35 percent of young people under 19. At the beginning of the twenty-first century, the challenge of providing for a dispersed and increasingly diverse population continues, and there will be added challenges concerning the most appropriate balance of education beyond school, for a wider population.