or private. Public schools are free but private schools' admission fees change from school to school. Foreign languages taught at private schools are usually at a higher level than at public schools since most private schools prefer hiring native speakers as teachers. There are five core subjects at sixth and seventh grades: Turkish, mathematics, science, social studies, and foreign language. At eighth grade, social studies is replaced by "Turkish History of Revolution and Kemalism" (). In the academic year 2001–2002, 10.3 million students were being educated and 375,500 teachers were employed in 34,900 schools. Secondary education Secondary education includes all of the general, vocational and technical education institutions that provide at least three years of education after primary school. The system for being accepted to a high school changes almost every year. Sometimes private schools have different exams, sometimes there are 3 exams for 3 years, sometimes there's only one exam but it is calculated differently, sometimes they only look at your school grades. Secondary education aims to give students a good level of common knowledge, and to prepare them for higher education, for a vocation, for life and for business in line with their interests, skills and abilities. In the academic year 2001–2002 2.3 million students were being educated and 134,800 teachers were employed in 6,000 education institutions. General secondary education covers the education of children between 15 and 17 for at least three years after primary education. General secondary education includes high schools, foreign language teaching high schools, Anatolian High Schools, high schools of science, Anatolia teacher training high schools, and Anatolia fine arts high schools. Vocational and technical secondary education involves the institutions that both raise students as manpower in business and other professional areas, prepare them for higher education and meet the objectives of general secondary education. Vocational and technical secondary education includes technical education schools for boys, technical education schools for girls, trade and tourism schools, religious education schools, multi-program high schools, special education schools, private education schools and health education schools. Secondary education is often referred as high school education, since the schools are called lyceum (tr: lise). In public high schools and vocational high schools, students attend six classes each day, which last for approximately 40 minutes each. In Anatolian high schools and private high schools, the daily programme is typically longer, up to eight classes each day, also including a lunch period.