On Demand courses are video or audio courses that you can take play and listen to when you have time. NASBA considers on demand videos and audio courses to be self study CPE. Self Study CPE, as you know, requires that you take and pass an exam to earn a certificate.
Typically, course materials include the video or audio file, Review and Feedback questions and a copy of the CPE exam. Depending on the course, it may also contains a PowerPoint presentation or an Excel file.