When Silverchair wrap up their mopey opening track with the words “lessons learned,” it’s hard to suppress a sigh at the overt lyrical reference to Kurt Cobain’s “Dumb.” But Australia’s answer to Nirvana are going through some changes: Silverchair’s third album, Neon Ballroom, wants to prove that this grungeling power trio has continued to mature since it first began to experiment, with 1997’s Freak Show. The problem is that the kids can’t decide what they want to do when they grow up. Ballroom tries on a shopful of options: the ranting grind-core of “Spawn Again” and the punk thrash of “Satin Sheets”; the stadium-ready heavy metal of the first single, “Anthem for the Year 2000”; the lavish orchestration of “Emotion Sickness,” which includes David Helfgott (the schizophrenic classical pianist who inspired the film Shine) on keyboards. Some songs work, such as the silvery power ballad “Ana’s Song (Open Fire).” Others, like “Black Tangled Heart” (think “Black Hole Sun” meets “Heart-Shaped Box”), with its turgid, midtempo Weltschmerz, are just a bad fit. All in all, Neon Ballroom is about what you’d expect from a young band going through its awkward stage.