A select group of Indiana University students got an unexpected guest lecturer on Tuesday in the form of Indiana native John Mellencamp. The singer/songwriter appeared at Professor Glenn Gass' long-ru

A select group of Indiana University students got an unexpected guest lecturer on Tuesday in the form of Indiana native John Mellencamp. The singer/songwriter appeared at Professor Glenn Gass' long-running rock history course, which covers the roots of the genre up through the British invasion. Previous guests have included Neil Young, James Brown, Bo Diddley and Cheap Trick's Rick Nielsen.

Mellencamp owns a home and recording studio outside the IU campus in Bloomington. He has been a much more visible presence in the city in recent years, endowing the Mellencamp Pavilion athletic practice facility and performing for free on campus in 2000. Still, his appearance in Gass' class this week took more than 15 years to engineer.

"I've been hoping to have him in since the mid-'80s," Gass tells Billboard.com of the visit, which featured Mellencamp answering questions from students and offering anecdotes on a wide array of topics. "In fact, he is the one who set up Lou Reed's class visit in 1987, and several of his band members, especially Mike Wanchic and Kenny Aronoff, have come in over the years, but I was never able to get John in until now."

Gass says he feels the timing was right because of Mellencamp's latest Columbia album "Trouble No More," which was rooted in old blues and folk music, as well as the artist's recent online missive against the war in Iraq. "[Mellencamp has shown] his willingness to put himself on the line politically, which I really admire and which I think my students needed to hear -- that the tradition of artist-troubadours speaking out is still alive despite [radio and concert giant] Clear Channel's best efforts," Gass says.

In related news, Mellencamp will headline a Buddy Holly tribute concert Dec. 6 at the Drury Theater in Cleveland. Other artists on the bill include Marshall Crenshaw, Joe Ely, Jimmie Dale Gilmore, Wanda Jackson, Nanci Griffith and Lenny Kaye. The Bacon Brothers will serve as emcees.