MOVIES : Young and Restless : Natalie Portman is Hollywood’s favorite 14-year-old. But wouldn’t med school be as much fun?

Natalie Portman was just 11 when she starred in Luc Besson’s 1994 film, “The Professional,” portraying a child who’s taken on as an apprentice by the neighborhood hit man after her family is slaughtered by crooked cops.

Her next appearance was in Michael Mann’s recent “Heat,” where she played a poorly parented teenager who slits her wrists, and this weekend she turns up again in Ted Demme’s film “Beautiful Girls,” where she all but steals the movie from co-stars Uma Thurman, Mira Sorvino, Timothy Hutton and Matt Dillon. One imagines these experiences might have transformed Portman into one of those child stars who has been in and out of rehab by the time the braces come off their teeth, but such is not the case.

In an interview at a Beverly Hills hotel, the 14-year-old actress comes across as remarkably unaffected by the fact that a film career is apparently hers for the asking. Dressed in a smartly tailored suit given to her by designer Isaac Mizrahi for modeling in his recent ad campaign, she confesses, “I’m not a movie buff. I like movies but I’m not one of those people who sees every movie that comes out, and I’ve never studied acting.”

Her priority, in fact, is school. “In the past three years, I’ve only missed two months of school, so it’s not as if acting has taken over my life,” she says. “I just finished shooting Woody [Allen’s next] movie, so now I want to concentrate on school. I definitely intend to go to college, and I don’t plan to major in drama.

“I might major in math and I’m also seriously considering medicine,” says Portman, whose father is an infertility specialist. “I don’t know if I could live with acting my whole life because there are such huge periods between films. I see these 20-year-old actors who do nothing but smoke cigarettes and go to clubs every night while they wait for their next part, and I couldn’t stand living that way. I have doubts whether I want to do this for the rest of my life, but I do love it and don’t know if I could give it up. Acting is dangerous work because it’s addictive.”

Portman’s finely nuanced performance in “The Professional” made most critics snap to attention, although some found an element of impropriety in a provocatively dressed 11-year-old slogging her way through a grim story of drugs and murder.

“I understood what was going on so it wasn’t as if I was being used,” Portman says. “This girl is at an age where she’s just starting to learn about sexuality, but there’s nothing disgusting in the way it’s handled. I felt it was important to maintain her innocence and when I first read the script there were a few scenes I felt went too far, so Luc took them out.” (The original script included a nude scene and some killings committed by Portman’s character.)

After “The Professional,” Portman was offered the lead in the Adrian Lyne remake of “Lolita,” currently in production.

“I met with the director but I immediately told him there’s no way I’m gonna do this movie,” she recalls. “Kubrick’s film of the book is great because nothing is really shown, but this one will be explicit. He told me they’d use body doubles but I said people will still think it’s me, so no thank you.”

Of the violence central to both “The Professional” and “Heat,” she sagely observes, “We live in a violent world and violence can be used in film to direct our attention to that reality. But since the success of ‘Pulp Fiction,’ it seems like every movie has violence in it and it’s now used as a form of comedy--audiences are encouraged to laugh when people get their heads blown off. At a certain point, we have to laugh at bad things because it lessens the pain of realizing this is what our world is like--but still, it’s strange to hear people laugh at violence.”

Portman moves in a radically different direction with “Beautiful Girls,” which finds her cast as a precocious vamp who lives next door to Timothy Hutton, with whom she shamelessly flirts and who bestows her first screen kiss (a brotherly peck on the cheek).

“Natalie’s very smart and she knew exactly the right way to approach potentially difficult scenes,” says Hutton of his co-star.

Adds Ted Demme: “Natalie absolutely blew me out of my seat in ‘The Professional,’ and after one reading of the script for ‘Beautiful Girls,’ I knew she was the only actress who could play this character.”

Of Allen’s untitled fall film, which also stars Lukas Haas, Julia Roberts, Goldie Hawn, Alan Alda and Drew Barrymore, Portman says: “It’s an old-fashioned musical where people burst into song as they walk down the street. It was a little hard for me because my character wasn’t clear-cut and I had to figure out who she was with relatively little information. Woody told us to think of the script as just a skeleton and said, ‘If you can’t think of anything to say, then say this, but feel free to say whatever you want.’ I can’t tell you more because if I talk about Woody’s film there’ll be a ninja waiting at my apartment when I get back to New York.”

Allen is equally circumspect in commenting on Portman. “I’d never seen Natalie in anything prior to the first time we met when she came in to interview, but she immediately impressed me as an unusually natural and intelligent actress--she has a great future,” he says.

Born in Jerusalem to an Israeli father and an American mother, Portman began studying dance when she was 4 and was signed to the Wilhelmina Agency six years later when a Revlon representative spotted her in a pizza parlor.

“When I was little I was so uninhibited I could do anything in front of people, but now I have terrible stage fright,” says Portman, who lives with her family on Long Island. “I’d love to do a play, but I have nightmares about missing lines onstage, even though the first job I ever had was onstage as the understudy in the original off-Broadway production of ‘Ruthless.’

“The anxiety I now feel about acting has nothing to do with movies, though--it’s just a part of getting older. You become aware of your body changing and of the fact that people are judging you--and you’re really aware of that when you’re in the public eye.”

As to whom she hopes to work with in the future, she says, “I’d love to be in a John Waters movie, and my favorite actor is Ben Kingsley--I’m not into that whole Brad Pitt thing,” she apologetically admits. “When I met Ben Kingsley I was so overwhelmed I just started crying, and he was really sweet and tried to comfort me. I also totally fell in love with John Turturro in ‘Unstrung Heroes.’ I went to see it with my best friend and at the end we looked at each other and just started bawling.”

It was, no doubt, a rare outburst for this otherwise extremely poised young lady.

“Acting probably is making [me] grow up faster than I normally would because I’m around adults so much of the time,” she says. “I’m friends with people much older than me, but they’re all quite intent on maintaining my innocence. Yesterday Ted Demme told me that if anyone ever did anything bad to me, I have 20 big brothers who’d rush to my rescue.”*