The Keystone School is an online high school and middle school program that prepares students for success – in college and careers. The hallmark of our school is flexibility. Through our online high school and middle school courses, Keystone students can study anytime, anywhere. With access to over 120 engaging online courses all supported by certified teachers, Keystone students can enroll full-time to earn an accredited online high school diploma or part-time to supplement traditional school or home school curriculum.