Hannah Montana Tour in San Diego

'This next song goes out to you guys, whatever it took you to get here,'' said Miley Cyrus, midway through the Nov. 8 leg of her Hannah Montana and Miley Cyrus: The Best of Both Worlds tour. Parents at the San Diego Sports Arena who'd maxed out their home equity, rolled over an IRA, or held up a liquor store to meet scalpers' prices understood that this was their shout-out. (Good seats for the 51-city jaunt are regularly being resold in the $300-800 range.) The defense for such madness: You can't lowball euphoria, as shared by thousands of shrieking preadolescents and at least a smattering of their chaperones. It's an ear-piercing roar familiar to anyone who remembers boy bands, Beatlemania, or bobby-soxers — only the critical difference here is that the din is for a fellow girl, one still part of her own 6-to-14 target demo. Tween neofeminism, thy name rhymes with Kylie.

Though Cyrus may be a live-action Disney princess, the 14-year-old superstar is also a determined and likable performer who can command a stage for 80 painless minutes. To answer your pressing question: She definitely sings live, though prerecorded vocals were likely mixed in with the background singers' contributions. Her sweat? Also real, the choreography at least 10 grand jetés beyond VMAs-level Britney. As rock, much of the music is kinda convincing. Call her Avril with training wheels, if you will, but some of these power-pop songs — however lyrically insipid — have rock hooks that Lavigne would kill for. (While Cyrus has probably never heard a Joan Jett record, whoever taught her to say ''Oww!'' surely has.)

Cyrus also has her eyes fixed on a post-Montana, non-Mickey-Mouse-beholden career. Halfway through her set, she chucked her character's blond wig and inspirational bromides for her own brunet tresses and boy-trouble ''solo'' offerings, lifted from the Hannah Montana 2 soundtrack's second disc — credited to (and co-written by) Cyrus herself. To her merit, dropping the illusion didn't diminish her fans' ecstatic screaming. In either guise, Cyrus' precocity can be freaky, what with her enormous self-possession and the fact that she's got the husky speaking voice of a 35-year-old Tennessee barmaid. So it was especially sweet when, for the encore, she ditched the dancers and enhancers and strummed an acoustic guitar on ''I Miss You,'' vulnerably serenading her late grandpappy — and, for once, really looking and sounding 14. Not everyone noticed because, when she finished, half the seats were empty. A chunk of parents might have spent four figures to get here, but this was a school night.