Nowadays computer users prefer to learn or complement their studies with video materials. While there are many video e-learning resources available on the internet, video sharing platforms such as YouTube which provide these resources, do not structure the presented material in the prerequisite order. Furthermore, they do not track the background of the users when recommending the next material to watch. Our aim is to overcome this limitation of the existing video on demand systems. In this paper we describe the architecture of the e-learning system that we are developing which allows users to search and watch video materials organized with respect to their background and presented in prerequisite order. One of the key features of our e-learning platform is to enable users to explore the video content with mobile devices. We propose a new visual metaphor based on lists for mobile devices which reflect the prerequisite graph structure, utilizing the limited screen size more effectively.