Claroline is a collaborative eLearning and eWorking platform (learning management system). It allows hundreds of organizations worldwide ranging from universities to schools and from companies to associations to create and administer courses and collaboration spaces over the web. The platform is used in more than 100 countries and is available in 35 languages.
Claroline is released under GNU GPL ver 3.0 and developed in PHP on the LAMP stack. It has a clean interface and is easy to install.