Previous classes haven't taken Eugene's change-the-world assignment seriously, but this year Trevor McKinney, a latchkey kid, does. At 11, Trevor is one of the smallest and youngest kids in his class. And with AWOL parents, he is wise and serious beyond his years. As Trevor, Haley Joel Osment, Oscar nominee for THE SIXTH SENSE, is amazing again. This role, however, isn't nearly as meaty as his last; so don't expect to see any nominations for him this time.

"So you'll like flunk us if we don't change the world?" Trevor demands to know in a quizzical panic. "No, you might just squeak by on a 'C,'" Eugene shoots back with a delicate mixture of sweet humor and biting sarcasm.

Trevor eventually comes up with an idea along the lines of a Good Samaritan chain letter. His simple plan is that people should do good deeds for three other people. His rules: "#1 it has to be something that really helps people, #2 something they can't do by themselves and #3 I do it for them, they do it for three other people." The only caveat is that people can't pay it "back." They can only pay it "forward," i.e., they must do something for someone else, not for the person who helped them.

Trevor's mother, Arlene (Helen Hunt), is one of the characters in need of a lot of help. She is an admitted alcoholic with an abusive husband and a woman whose only friends are other drunks. Working two jobs and drinking heavily when she is home, Arlene is rarely there for her son, either physically or emotionally. One of their mother-son confrontations will have parents (and kids) in the audience flinching and perhaps even shedding a tear or two. Arlene's husband, a fellow drunk, is currently in one of his long banishment periods.

Both Spacey and Hunt are made to look awful in the service of their craft. Arlene, especially after a long night of boozing, doesn't look the least bit like Helen Hunt. Although Arlene's make-up and clothes are convincingly terrible at first, she is spruced up too quickly, as if, in some scene left on the cutting room floor, she had a makeover by a beauty consultant. In contrast, as the story advances, Eugene shows even more of his deep physical scars.

Jerry (James Caviezel, FREQUENCY), the first person who Trevor tries to help, is a street person with a heavy drug habit. Eugene, Arlene and Jerry share several traits. Eugene hides the story behind his burns. Arlene hides her bottles like squirrels do nuts. And Jerry just hides, period, lest Trevor find him shooting up again. Similarly, Eugene lives for the rigidity of his precious schedule. Arlene lives for her next drink. And Jerry lives for his next fix. Trevor and his pay-it-forward scheme change all of this.

A parallel story, which starts slightly in the future, has a newspaper man (Jay Mohr), who is himself befriended by a pay-it-forwarder, tracking down the origin of the movement. Although it is an important adhesive for the storyline, this subplot never provides anywhere near the emotional or dramatic impact that it could have. Overall, Leslie Dixon's script, based on Catherine Ryan Hyde's novel, is much better with the dialog than the narrative.

One of the many sharply written interchanges between Trevor and Eugene occurs when Eugene incorrectly thinks that Trevor is questioning his sincerity. "Do I strike you as someone being falsely nice?" Eugene asks caustically. "No, you're not even really nice," Trevor replies with bitter honesty.

Although PAY IT FORWARD has more than enough to be able to recommend it, it does have two significant problems. First, major plot twists are needlessly telegraphed, destroying what would otherwise have been dramatic surprises. Second, the acting is frequently too subdued, and you can almost feel the director throttling back her cast. Yes, there are some definitely saccharine scenes, but many others that should have had significant emotional impact come across surprisingly lukewarm. This will probably be an unpopular opinion, but PAY IT FORWARD is that rare movie that would be more effective if it were schmaltzier.

PAY IT FORWARD runs a bit too long at 2:02. It is rated PG-13 for mature thematic elements including substance abuse/recovery, some sexual situations, language and brief violence. It would probably be too strong for most kids under 13.