If show business were high school (and isn't it, really?), Beyoncé would be a front-runner for valedictorian. She's a class act on and off the charts, a can-do girl who shares her gifts with everyone while keeping her beyond-fabulous life the Obamas on speed dial, Jay-Z at the dinner table largely to herself. Over the course of her three previous records, she's matured from Destiny's Child-hood into a formidable solo hitmaker with two of pop music's most transcendent chart-toppers, ''Crazy in Love'' and ''Single Ladies,'' tucked in the pocket of her Deréon jeans.
So why does it feel like Beyoncé is struggling so hard to prove herself on 4? The album is an every-song-for-itself welter of conflicting ambitions: It wants to be cutting-edge but familiar, accessible but artistic, hot-blooded but strictly impersonal. Those tensions hurt most in its lumbering first half, a defiant bird flipped at anyone expecting out-of-the-box radio killers. Instead, we get a sleepy recital of ballads, kicked off by the arid Prince-ipality of ''1+1'' and ''I Miss You,'' in which Bey pants and sweats and grunts (except, you know, sexy-like), her voice climbing ever higher in search of an octave big enough to hold it. ''I don't know much about guns/But I, I've been shot by you,'' she yelps on ''1+1,'' as if the love bullet were actually breaking skin. Vocally, she’s never sounded better throaty and precise but the songs here just aren't her equal.
While those efforts at least aim high, a few of 4's lesser tracks feel like they were unsuccessfully bred in studio captivity for mass consumption. The familiar lite-FM bombast of ''Best Thing I Never Had'' proves her 2006 hit ''Irreplaceable'' is just that. ''I Was Here,'' co-written by Diane Warren, reaches Lifetime-movie levels of schmaltz, while the promisingly named ''Party,'' featuring Kanye and Andre 3000, turns out to be a slow-jam invitation to an after-work mixer with light refreshments. And when the 29-year-old mimics Luther Vandross and Diana Ross on the charmingly goofy one-two of ''Love on Top'' and ''Rather Die Young,'' she gets lost in her idols' polyester-swathed shadows.
Unsurprisingly, Beyoncé is at her best when she sounds like no one but herself. She takes her trusty freakum dress out of mothballs for the marching-band funk of ''Countdown,'' which includes such joy-inducing non-lyrics as ''Me and my boof, and my boof boof riding.'' On ''Run the World (Girls),'' the first single off the disc, she turns cheesy postfeminism into a martial foot-stomper that crackles like a burst of pirate-radio agitpop. (It bombed accordingly on the mainstream charts.) And the terrific ''End of Time'' seethes with off-balance harmonies, MJ-style Off the Wall horns, and a bionic Bo Diddley beat, all while Bey howls her eternal love to everyone and no one in particular. It's exactly the kind of genre-busting risk that few other current pop stars would even attempt, let alone pull off flawlessly with a no-big-thing shrug. With more moments like that, 4 might have been an album fully worthy of her talent. As it is, though, even star students get the occasional B.