I randomly discovered today that former Microsoftie (apparently) Eric Artzt used Ruby on Rails last year to write a very pretty little student information system (well, part of one) named TinySIS for an alternative school in Seattle called The Nova Project as part of his work on a masters in ed tech.
The screen shots in this pdf look great. The only problem now is that despite describing how the project "Made me love the O.S.G (open-source goodness)," Artzt doesn't seem to have any plans to release his code as an open source project. Oh well. Another missed opportunity. I'm used to those.