Project Fedena is the open source school management system based on Ruby on Rails. It was initially developed by a team of developers at Foradian Technologies.
Also available some screencasts:
1. Introduction
2. Login to Fedena
3. Academic year migration intro
4. Create academic year
5. New Academic Year
6. Timetable
7. User management
More information here http://www.projectfedena.org/about
My opinion it's kind of promising project for school or college, will see what will be in future with it...