Keewartson's school uses HighSchoolSports.net as well. The entire school's actvities are posted including plays, staff meetings, and weekend activities. All students and parents are enourced to check it, especially for changes. The nice feature is that you can sort by sport and get the whole schedule, JV or Varsity. I believe all the school's in our county use it.
If you desire something different, you may want to check with MidloDad. He set up a fan based website for his son's school team several years ago.
Chefmike is right....not too eyecatching, though. Sounds like it could be a nice project for a web deisgn student project.