If you've seen Secondhand Lions, you've made one inescapable observation: Haley Joel Osment's voice has changed.

This should come as no surprise. Osment, perhaps the best child star of recent years (The Sixth Sense, A.I. Artificial Intelligence), is no longer a child star. He's 15, itching for the day next April when he can get his driver's license and determined not to become a child star frozen in time.

``As an actor, that's the last thing you want to do is stay doing the same character over and over,'' Osment said. ``The character, while you're doing it, is great, especially if you get to do a performance that you'll always be happy with. I'm very happy with Sixth Sense. But that's on its own. That can't be part of what you do afterward.''

That's the answer of a seasoned actor, one who's used to talking to the media.

In The Sixth Sense, he played a haunted child with such empathy and eeriness that his fear became part of the movie's chills.

Most actors wait a lifetime for roles like that; child actors sometimes never recover from them.

But Osment already has another beautiful performance to his credit, as the android who wants to be a real little boy in A.I. Osment added wonder, poignancy and even subtle terror to a character that could have been cloying.

Even when he's drowned by melodramatic mawkishness, as he was in the well-meaning misfire Pay It Forward, Osment transcends the story.

In Secondhand Lions, Osment is surrounded by some more melodrama, but there are also heavy doses of humor and adventure in writer-director Tim McCanlies' story about a shy teen who spends a summer with a couple of eccentric uncles. Osment's role shares an earnestness with his other best-known work, and as talented as he is, he risks typecasting and even critical backlash, which is something a teen shouldn't have to worry about.

Not that Osment does.

``I think most actors don't pay too much attention to reviews,'' Osment said. ``It's good to know the response that you get. But there's so many reviews, and they're so varied, and you don't know what causes people to respond a certain way. So it's really good not to take them too seriously, good or bad.''

Osment would like to play a villain someday, but opportunities for that kind of role are limited in his age group.

Osment has been fortunate to work with directors who are sensitive to young actors, including McCanlies, who directed four up-and-coming stars in the regional hit Dancer, Texas, Pop. 81 a few years back.

With Lions, McCanlies aims for something bigger, and that includes bigger stars, such as Michael Caine and Robert Duvall, who play Osment's uncles. These are people who are a little more intimidating and experienced -- and McCanlies counts Osment among them.

He said it was interesting to see the bonding between Osment and the older actors, especially Caine. ``They were both nominated for an Academy Award the same year,'' McCanlies said. ``So they were always peers, from minute one. I think Bobby (Duvall) wasn't sure about working with a kid at first, but very quickly, when he found out who Haley is and how great he is... they were really three equals. They were all peers, and they talked to each other like peers.''

Osment has a reputation for professionalism and politeness, both on the set and during interviews.

``It's really just what I've learned being around these people, though,'' said Osment, whose co-stars have included Bruce Willis, Helen Hunt, Toni Collette and, on TV, Edward Asner and Candice Bergen.

``That professionalism comes from what I've watched people do on the set. I'm just trying to be as respectful to the environment, as they have been. I think I still act like a kid. I just try to be as professional as I can.''

The true grounding element for Osment is his family, especially his father, Eugene, who doubles as an acting coach and has a bit part in Lions. He's determined that his family won't implode, the way families of young stars sometimes do. (Haley's younger sister, Emily, also acts, appearing in two of the three Spy Kids movies).

``It's very hard to get through this business without having support,'' Osment said of his family.

And he hasn't missed out on childhood. He's big on video games and has loaned his voice to at least one of them; he's also a jock, getting into golf, cross-country racing and soccer. He takes his guitar along when he's filming on location (his musical tastes lean toward Radiohead, Coldplay, R.E.M., Pink Floyd and Led Zeppelin).

But he really becomes engaged when the conversation turns to history. He and his father traveled to Poland in 2000 to work on Edges of the Lord, a Holocaust drama. The movie, which is being held up over legal matters, stirred Osment's interest in history, a subject he thinks some teens are missing out on.

``I read some fact recently, that even despite the big blitz of information that has been put out there by people trying to raise awareness of these things, I think it was like 30 percent of high school graduates in the United States tested that they knew what the Holocaust was,'' Osment said. ``That's appalling, that something that catastrophic in history is unknown to modern people. It's because there's so much indifference to the past, and that's just a recipe for disaster.''

Osment then begins to discuss genocide in North Korea and Africa, and about that time a remark by Osment's Pay It Forward co-star Kevin Spacey -- who called Osment ``a 40-year-old midget'' -- starts to sound accurate.

Osment credits his parents for teaching him to read early and his teachers for inspiring a love of reading, and he criticizes the funding of U.S. public schools. That's when he begins to sound like the Yale student he aspires to be.