Charlie Bartlett (15)

Anton Yelchin is a cheeky pup. At the time of writing, there is no vacancy for a new Jim Carrey, the current model having oodles of zip left in him the last time anyone checked, but that doesn't stop 19-year-old Yelchin auditioning for the role in the coming-of-age tale Charlie Bartlett.

But then, trying to be what you are not is something of a motif in this likeable if lightweight picture. Just as Yelchin, playing Charlie B, sticks his fingers into the sockets of comedy like Carrey, so Jon Poll's movie aspires to levels of coolness last seen in Rushmore and Ferris Bueller's Day Off. The only person being himself is Robert Downey Jr, but even he is playing a version of the real life individual he used to be, complete with demons on his tail.

After yet another incident at a private school, Charlie is preparing to try his hand in the state sector. Rich, perky, sensitive, with an eccentric streak a mile wide, he has about as much chance of blending into the tribal badlands of a state high school as Dick Cheney has of being the next director of Amnesty International. As Charlie says of himself, "My family has a psychiatrist on call, how normal can I be?"

Said trick cyclist prescribes medication for what ails Charlie. No-one is entirely sure why he is so unsettled. He lives in a fabulous house with a doting if dotty mother (Hope Davis), but there are hints about a missing father and Charlie has just been beaten to a near pulp by the school bully. The diagnosis settles on attention deficit disorder and drugs are dispensed. Though meant to soothe his nerves, the medication makes Charlie go loco, and it's at this point we're treated to the full Jim Carrey act. While not a bad attempt, it's still sending a boy to do an expert's job.

The unfortunate experience with medication switches Charlie on to a new way of winning friends and influencing people. Instead of taking the drugs himself, he'll sell the stuff to his fellow pupils. Charlie is a drugs tart with a heart, though. As well as dispensing pills, he sets up his own counselling practice in the school toilets. The scenes of Charlie in session, his "patient" in the cubicle next door, are smart, tender, funny, and bang on the money about teenage woes. Suddenly, Mr Bartlett is Mr Popularity. Like he says, "Bringing psychiatric drugs and teenagers together is like opening a lemonade stand in the desert."

Not everyone is buying Charlie's nice guy act. The lead doubter is his headmaster, played by Robert Downey Jr. Bored and frustrated with his paper-pushing job, and with a daughter (Kat Dennings) who is keen on Charlie, the head has reason enough to dislike his newest pupil. But this being a touchy-feely movie of the modern school, Downey Jr has to connect with Charlie on a deeper level, flawed mano a mano. Sir has a dependency problem of his own, and it's not excessive use of the photocopier.

There's something vaguely insulting to the intelligence of both the audience and Downey Jr in asking him to deliver lines like: "Being zonked out of your mind is a lot better than dealing with your problems". Perhaps roles like this one, and most recently in Zodiac and Iron Man, are meant to be ironic choices for an actor who had his own, highly publicised, walk on the wild side. If so, one hopes Downey grants himself absolution soon. He's too brilliant and original an actor to be typecast by the past in this way.

Downey shows his class in the scenes with Yelchin. Though the youngster makes a fair attempt at playing someone on the edge, the Chaplin star demonstrates how it's really done, slowly peeling the layers off his character, making his plight believable and the reactions understandable.

Well, almost. The drama becomes increasingly overheated as writer Gustin Nash and director Poll, making their feature debut, strive to bring matters to a series of neat conclusions. Even though this undermines the film's message, that life is a tangle that sorts itself out eventually, the urge to tie things up in a bow proves irresistible.

For Matthew Broderick in Ferris Bueller's Day Off, bouncing back meant driving a fast car, singing a Beatles song, and being with your best girl and best friend. Simpler times, simpler teen dramas.

Charlie Bartlett, like others of its kind, feels the need to be the voice of a generation, in this case the generation hit by a chemical cosh. Nothing wrong with that, but the way it goes about the job, as if this was an episode of The Waltons rather than a movie in its own right, is unduly earnest. Sometimes, as Ferris said, it's enough just to stop and look around once in a while, no lectures required.

Anton Yelchin as the hero of the title makes a big impression in this lively but patchy comedy.

That's no mean feat in a cast that also includes inveterate scene stealers such as Robert Downey Jnr, and Hope Davis.

Charlie is expelled from his private school after a fake ID scam and ends up in the local state school. A bit of bullying brings him to the attention of the school therapist, who promptly writes him a prescription for anti-depressants.

Sensing another scam Charlie sets himself up as a part-time psychotherapist dispensing drugs and advice in equal measure to his classmates.

Inevitably, Charlie crosses paths with Downey as the school's embittered principal. Its lively stuff with some nice moments, especially from Yelchin.