Ah, to be young. Your skin is wrinkle-free, your cynicism hasn't completely overtaken you … and, if what happened in the "American Idol" semi-finals is any indication, you’ve got some seriously strong pipes.

Sure, I know everyone on "Idol" is young. And of course I remember that last year's winner, Jordin Sparks, wasn't exactly elderly. Still, it's definitely clear that the 18-and-under crowd is really ruling the "Idol" roost so far.

Taking the lead is the unbelievably cherubic David Archuleta, who we know is a human being because he looks and acts like one but in many ways seems more like a precious doll or plaything.

Click here for photos of the top 24 contestants.

To get an idea of what David's like, take the most bashful person you know, add a dash of Melinda Doolittle, mix in some dimples and you're left with this 17-year-old who's as earnest as a Hallmark card.

Archuleta perfectly fills that whole innocent, prepubescent Sanjaya-Kevin Covais role. But unlike some of those other boys (sorry Sanjaya lovers — all two of you that may be left), this one definitely delivers the goods. Which is a good thing — because otherwise, his gee-gosh-you-really-like-me thing might really get old.

Then there's Alaina Whitaker, a 16-year-old dead ringer for Carrie Underwood, who may have come off as cocky during her original audition (Simon told her she wasn't as good as she thought she was) but is more than rising to the occasion now. In fact, the judges in a rare moment of complete agreement all sang her praises.

Our trio wasn't all behind 17-year-old Alexandrea Lushington, but I have to say she's the one whose transition wowed me the most. During the auditions, she was cloaked in an army green jacket and seemed relatively demure; quite honestly, her sweet great-grandma made more of an impression than she did.

But on Wednesday night, she came out rocking a whole new look, which seemed to be accompanied by an entirely different personality. Clad in a hip T-shirt, skirt and suspenders with her hair piled on top of her head and an enormous peace earring dangling from her ear, the girl really worked the stage like a pro.

An uncharacteristically astute Paula said it well: Alexandrea just took control from the moment she came out there. While Simon ripped into her a bit, even he had to admit that the girl's personality — she managed the nearly impossible feat of having attitude but not coming across as either snobby or precocious — was stellar.

I'm still holding out hope for 18-year-old Kady Malloy, who delivered an extremely dour rendition of "Groovy Kind of Love" but was shown off-stage doing hilariously accurate Britney Spears imitations that displayed her talent a whole lot better. The judges encouraged her to fun it up and though she stared daggers at them, I get the feeling she'll take that advice to heart.

At least I hope she does. Because otherwise, there is a slew of even younger kids nipping at her heels.

Anna David is a freelance writer. Her novel, "Party Girl," is in stores.