Teenagers are faced with some tough life choices, but there aren't many who have to pick between attending their senior prom or hosting NBC's "Saturday Night Live." But, of course, Mary-Kate and Ashley Olsen aren't average teens. Minimoguls virtually since birth, the duo has seen their Dualstar Entertainment Group grow into a billion-dollar venture with global reach.

Now, as they accept their star today on the Hollywood Walk of Fame in front of the Hollywood & Highland entertainment complex, the Olsen sisters are indeed at a crossroads. Turning 18 on June 13, they are about to take full control of their multimedia empire while simultaneously rolling out their first major motion picture, the May 7 Warner Bros. Pictures release "New York Minute," in which they star and share a producer credit.

"Even though they're still teenagers, they've been working in this business almost all of their lives, and their instincts, talent and perspective have been shaped by everything they've learned along the way," Warners president of production Jeff Robinov says.

That knowledge will be put to good use this summer when the duo assumes the role of co-presidents at Dualstar, which was launched in 1993 to create projects for the then-child actors to star in and produce.

Thanks to the countless books, videos, CDs, TV shows and direct-to-video features -- not to mention ancillary merchandising -- distributed through Dualstar, the girls are poised to take control of an estimated $150 million when they come of age. Of the girls' success, Dualstar CEO Robert Thorne says: "I think it's really phenomenal, but I don't think it's a phenomenon because this was planned."

The planning was done largely by Thorne -- the one-time attorney who has shepherded the girls' career. In 2003 alone, the privately-held mary-kateandashley brand earned more than $1 billion at retail; overall, it is estimated to be worth $300 billion. The brand, which is distributed by Wal-Mart, includes more than 50 merchandise categories, including fashion and housewares. Thorne estimates that last year, the twins outsold Sean Combs' Sean John line by more than $450 million. In 2002, the twins, then 16, made Forbes magazine's list of highest-paid entertainers and athletes.

"They kick-ass," Thorne says enthusiastically. "You know, it's OK to sell school supplies if that product brings in millions of dollars in revenue. People think, 'Holy Toledo!' That's formidable."

Having conquered the ancillary markets, the Dualstar team has now set its sights on the big screen. In "Minute," they play look-alike sisters with opposite personalities who accidentally become caught up in a wild chase through New York over the course of one day.

It's a film the sisters managed to crank out while completing their senior year of high school.

Between studying for final exams, rehearsing for their "SNL" gig (the duo is hosting the show's season finale, May 15) and taping an appearance (that aired yesterday) on "The Oprah Winfrey Show," it's no wonder they were too busy to sit for an interview with The Hollywood Reporter during the weeks preceding their film's release, answering questions only via e-mail.

The topic the sisters were most interested in discussing was their new role as feature filmmakers. While the girls were used to calling the shots on their direct-to-video movies -- which Dualstar produced independently and distributed through Warner Bros. -- producing on a feature-film scale was new for them, and they were smart enough to call in a pro, securing industry veteran Denise Di Novi (the planned July release "Catwoman," 2003's "What a Girl Wants").

That's not to say the girls don't have a firm hand in the decision-making process, according to Mary-Kate, who says, "Probably the biggest misconception about us as producers is that it is just a title. We've been learning this job since we were 6 years old, and we feel we make an important contribution to what the audience will see onscreen."

On "Minute," whose budget reportedly ran $40 million, Ashley says, "Everything was bigger, and we had to collaborate with executives at Warner Bros., which was a new thing for us. With the direct-to-video features, we generally had the final say on creative and business matters."

"Minute" director Dennie Gordon concedes that the girls had a surprisingly strong voice. "Oh, they grilled me!" she laughs. "They really worked me over; I wasn't ready for that." Gordon says the Olsens are very aware of whom they are, and that their self-confidence as young women is what makes them stand out. "I always say, 'You underestimate these girls at your own peril,'" she says.

Dualstar senior director development and production Jill Zimmerman says that on "Minute," the girls had a clear idea for the tone of the movie and made sure their opinions were heard. "Mary-Kate came up with the idea of asking Ozzie Osbourne fils Jack to be in the film, and they both fought hard for veteran funnyman Eugene Levy as their zany high school truant officer," she says.

That said, the feature realm was a complete learning curve for the twins, according to Zimmerman, who feels the results will prove to many that the Olsens' place among Hollywood's heavy hitters is no fluke.

To reinforce their grown-up image and new role among Hollywood's power players, the twins -- who are technically fraternal, not identical -- have been cultivating individual identities. In fact, Mary-Kate recently adopted a brunette hairstyle that makes it easier to tell the two apart. And their penchant for parties, if not "partying," has been a focal point of consumer press interviews.

Gordon sums up their individualities by stating: "Mary-Kate is a total director, and Ashley has such unbelievable physical comedy talent."

Now that the girls are embarking on their own real-life Mary-Kate and Ashley adventure, they are relishing the freedom to try new things and reinforce their place as serious businesswomen.

"I think we are equally comfortable in front of or behind the camera. We've been able to do both for our whole careers, so I expect we will continue to do both as we get older," Mary-Kate says. They both concede, however, that acting is their first love.

As far as being officially named co-presidents of Dualstar, the twins shrug it off like "it isn't a big deal," Ashley says. "We have been functioning in that role for years now." Indeed, the girls have juggled their studies with executive-level policy-making from the very beginning of the 47-title "Adventures of Mary-Kate and Ashley" video series, all the way up to present-day decisions on whether to have a London fashion show for their summer clothing line (yes) or if their likenesses should be associated with branded food items (pass).

"I talk to them 10 times a day. Between the Blackberry and the phone, I am in contact with them constantly," Zimmerman says.

This fall, both sisters will join the ranks of New York University's freshman class of 2008, an experience they are both looking forward to beginning. "There has always been a great system in place for us, so that we could remain involved in our business and still stay focused on school. I don't expect that to change when we are in New York at college," Mary-Kate says.

Dualstar has already purchased office space near their residence, so the co-eds will be able to continue to work between classes. It is currently being refurnished. "Their office will be equipped with video conferencing," Thorne says. "They want to get up in the morning, have a mocha cappuccino or whatever it's called, talk to Japan, then go to their morning class." Now that the girls have grown up, Thorne looks back at their formative years under the media microscope with equanimity, "It's 'The Truman Show' that went right."

While in school, the sisters will be enrolled in a specialized program that allows them to choose much of their own curriculum, though the expected majors of film and business might not be in their futures.

"I feel like I already have a masters in business," Ashley says.