It seems like just yesterday that Miranda Cosgrove was the sharp, witty 8-year-old manager of Jack Black's "School of Rock" band. Now, the actress is almost all grown up, and with the hit Nickelodeon show "iCarly," and a solo album in the works, she's on our list of girls who may just be hot on the heels of Miley Cyrus.

You've already heard her voice on the" iCarly" theme song and soundtrack, but this 15-year-old (who was discovered singing at the ripe age of 3) is eager to show some creativity with her upcoming album, which may include a collaboration with Boys Like Girls.

"Actually, with the 'iCarly' soundtrack, I didn't get to write any of the songs. I just picked songs that meant a lot to me that I really liked," Cosgrove told MTV News. "Now, for my own CD, I've been co-writing and getting really into it. It's still pop-rock fun music like the 'iCarly' soundtrack, but I think it's a little more mature. They're love songs and just fun songs about hanging out with your girlfriends."

"iCarly," a show about a girl with her own Web show, has struck a chord with the tween crowd — it's #3 in the demographic, behind just "American Idol" and "Zoey 101" — and has proven to be more than just a TV series. Through iCarly, viewers can become a part of the pseudo-reality show by uploading their own videos demonstrating their talents (one such contribution featured a guy squirting milk out of his eye).

"[The user videos are] a really a big part of it," Cosgrove said. "It's the first reality-type show where kids can send in videos and really be a part of it. People can do pretty much anything, like the milk thing, or playing guitar and singing, or inventing something and cooking."

While juggling her work on the screen and in the studio, Cosgrove attempts to keep up with life as usual: She has afternoon get-togethers with friends and still plans to attend college. And rather than get overwhelmed with comparisons to Miley Cyrus, the multitalented Cosgrove says she'd like to focus on her acting — and take everything one day at a time.

"I really think it's cool when I go to the mall, and kids come up to me and say the episodes they like and talk to me about how much they enjoy the show," she said. "It's just such a good feeling to know people are actually watching."