From TV Guide: Keck’s Exclusives: The Vampire Diaries: Happy Graduation?
The bigger question is, which of the seniors — Elena, Stefan, Caroline, Matt, Bonnie and Rebekah — will actually make it to the big event, which airs May 16? “Definitely not all of our wayward, delinquent students will be present when it comes time to collect their diplomas,” Plec says. “I’m not saying they won’t be alive — they just won’t be able to extricate themselves, as graduation falls right in the middle of a crucial supernatural time.”
Next season, Diaries will tear a page from the 90210 playbook by having some of the students enroll at a nearby university, Whitmore College.
For the records, Whitmore College is a college Jenna attended. It is also the same college where Sheila Bennett taught Occult Studies. It was seen for the first time in “The Five”. In “Catch Me If You Can”, it is implied, if not indirectly stated, that the college is not in Mystic Falls, as Sheriff Forbes could not legally arrest Shane on campus, because they were outside her jurisdiction. (source: TVD Wikia)
And on a side note, Stefan’s last name in the casting call was originally Whitmore instead of Salvatore. (source)