After middle or junior high school, U.S. students go to high school. Going to school is free in the United States, including high schools. Students do not need to pay tuitions, and even textbooks and lunches are free. Of course, we are talking about public schools. If parents choose to send their kids to private schools, they need to pay very expensive tuitions. High school is the last four years of school that students in the U.S. are required to attend by law.