The RN-to-BSN courses have been designed to meet the American Association of Colleges of Nursing (AACN) Baccalaureate Essentials and to support the transition into the graduate-level nursing courses for those who wish to pursue continued education. Aspen updated their overview recently which has a pretty comprehensive overview. http://www.aspen.edu/degrees/bachelors-degree/bachelor-of-science-in-nursing-completion-program
Mary Jean brings up a good point. Each school's program is very different. At Aspen, there are no quizzes, no statistics courses, and no "hard" science courses. A bulk of the work is written in the form of discussion posts and a Capstone project. It's liberal-arts based, and it serves nurses who thrive in a more open and creative environment.
Aspen University has one of the most affordable and convenient online RN-BSN programs available. You can study at your own pace and courses start every 2 weeks so you don't have to wait for a semester to start.