OK, so it's a bit irreverent to call the influential German composer/critic Robert Schumann "Bobby," but why not, given the unique nature of a 10-hour Music Marathon that pays tribute to one of the greatest of all Romantics and his classicist predecessor (and movie star) W.A. Mozart? Local professional pianists, teachers and students perform solo and ensemble piano works by both giants for 10 straight hours, with professionals playing mini-recitals at the top of each hour. This marathon commemorates the twin anniversaries of Mozart's birth (250 years ago) and Schumann's death (150 years ago). Drop in for at least a set or two, if only to catch some of Schumann's haunting and introspective compositions. (The guy "discovered" Chopin, for crying out loud, so you have to trust his musical sense.) Sat., Feb. 25, 9 a.m.-7 p.m., The Music Center, St. Pete College-Gibbs Campus, 6605 Fifth Ave. N., St. Petersburg, $1, 727-328-2387.