Arapahoe High School is a public high school in Centennial, Colorado, United States. Located in a suburb of Denver, it is the flagship of the Littleton Public Schools District as the largest of three high schools, with an enrollment of 2,229 students. It has been designated a Blue Ribbon School by the U.S. Department of Education. The school is known for its affiliation with the Arapaho tribe of Wind River, Wyoming.