Sugar is the core component of a worldwide effort to provide every child with equal opportunity for a quality education. Available in more than twenty-five languages, Sugar’s Activities are used every school day by nearly three million children in more than forty countries.
Originally developed for the One Laptop per Child XO-1 netbook, Sugar runs on most computers. Sugar is free/libre and open-source software.
For hacking you can use the sugar-build tool. Sugar is made of several modules and it often depends on libraries which has not yet been packaged in linux distributions. To make it easier for developers to build from sources, we developed a set of scripts that automates builds and other common development tasks.
For details see: http://developer.sugarlabs.org/dev-environment.md.html