Founded in 1985, Edge High School is a tuition-free, charter high school operated by The Edge School, which is an independent, nonprofit organization. Edge High School provides instruction for students in grades 9 through 12. Its students attend school four hours a day and can choose morning or afternoon schedules to fit their needs. Each of its applicants educational skills are assessed with the tests of adult basic education during the admission. Its teachers use grade-level scores in reading, math and language arts to diagnose areas of deficiency for program placement. Edge High School is affiliated with the Pima County Adult Education and the Pima Community College. It is accredited by the North Central Association. Edge High School is located in Tucson, Ariz.