E-learning has the potential to offer significant advantages over traditional classroom learning. However, it requires a complete redefinition of the dynamics of interaction between the various actors of a classroom. Moreover, in this context, the authoring of instructional material requires much more time than in traditional learning. Therefore, special care has to be posed to the definition of proper authoring approaches where educators can reuse and easily assemble existing materials. In this scenario, a comprehensive learning platform addressing the various interrelated aspects of authoring and fruition of instructional material is needed. Such a platform should enable reusability of materials, so that it is possible to make efficient use of preexisting experiences, and interoperability with existing platforms so that it is possible to take advantage of their strengths. The SCORM standard offers, among other features, a rich data model that can be used to define and share Learning Objects through different e-learning platforms. We argue that, despite the fact that it is the most emerging and promising standard, SCORM does not address some key issues properly, such as specification of metadata and LO composition. In this paper we focus on these issues and propose some extensions to SCORM that aim to address the above issues.