Specification of learning trails in virtual courses

Lifelong learning and goal driven learning create new requirements for virtual online courses. The development of virtual courses is not just a technical challenge, but is also a didactic and pedagogic challenge. In order to cope with the requirements met by heterogeneous student groups of online courses, learning trails are classified, which guide students through a course in different ways. A learning trail can be oriented to the didactic structure or the structure of the subject's scientific domain, to learning units of the same type such as conclusions or exercises, to selective or modal structures. This enables students to use the some online course in a productive and effective way. L3-XML, an XML-DTD, is presented to specify an online course enabling different learning trails. The concept is demonstrated for the "Introduction to object oriented programming" course.