Michigan's education system provides services to 1.6 million K-12 students in public schools. More than 124,000 students attend private schools and an uncounted number are home-schooled under certain legal requirements.[137][138] The public school system has a $14.5 billion budget in 2008–2009.[139] Michigan has a number of public universities spread throughout the state and numerous private colleges as well. Michigan State University has the eighth largest campus population of any U.S. school. Seven of the state's universities—Central Michigan University, University of Michigan, Michigan State University, Michigan Technological University, Oakland University, Wayne State University, and Western Michigan University—are classified as research universities by the Carnegie Foundation.