Education is free and compulsory for children between the ages of 6 and 16, and an additional two years of free education are optional. In 1997, 101 percent of Malaysian children attended primary school. Parents may choose between Bahasa Malaysia, Chinese, or Tamil as the language of instruction for their primary-school children. Bahasa Malaysia is the primary language of instruction in all secondary schools, although continued learning in Chinese and Tamil is available and English is a compulsory second language. Enrollment in secondary education was 64 percent in 1997. Malaysia has a number of institutions of higher education, including nine universities. Universities include the National University, in Bangi; the University of Technology, in Johor Baharu; and the University of Malaya, in Kuala Lumpur.