Hollywood gets plenty of flack for promoting violence, irresponsible sex, unfettered greed and countless other anti-social behaviors. So it seems a refreshing departure, if not borderline revolutionary, to find a major Hollywood release promoting basic human kindness. That’s exactly what Pay It Forward does; to “pay something forward,” you see, is the opposite of paying it back. You help someone, asking not that they pay you back, but that they pay it forward by doing someone else a good turn. In Mimi Leder’s film, based on the novel by Catherine Ryan Hyde, that philosophy is the brainchild of 11-year-old Trevor McKinney (Haley Joel Osment), who lives in a working-class Las Vegas neighborhood with his mother, Arlene, a recovering alcoholic (Helen Hunt). On the first day of seventh grade, Trevor’s social-studies teacher, Mr. Simonet (Kevin Spacey) gives his students an assignment: Think of an idea for changing our world and put it into action. He invites them to take something they don’t like about the world and flip it upside down. But that assignment ultimately flips Simonet’s own neatly ordered world upside down as his students show him realms of expanded possibility. Trevor’s idea is to do something nice for three people, who will then promise to do something nice for three other people, and so on. He first targets a homeless drug addict, whom he invites home for breakfast. His next subject is Mr. Simonet himself, whom Trevor hopes to set up with his mother. His third target is an asthmatic friend who keeps running afoul of the school’s bad boys. But through the power of exponential math, his notion of paying it forward eventually mushrooms into a national movement. The blue-blooded Hunt takes on a very different role as a busty, miniskirted, self-described “white trash” cocktail waitress working two jobs to support herself and her son. She’s in recovery, but she’s still a closet drinker who hides vodka bottles around the house to help her cope with her dreary existence. In one scene, when Trevor wakes his mother up after a bender, Hunt looks so shockingly haggard you hardly recognize her. Spacey is remarkable as the scarred teacher whose Ivy League speech and placid exterior belie a frightened and insecure man. His manageable routine is all he has. His reluctant courtship of Arlene is touching, but no scene resonates more than when he opens his shirt to her. His face clearly reflects the huge risk he is taking, as hers reflects complete acceptance. In the end, Leder’s film does become a predictable romance. But to see it only in those terms is to miss its primary message: that a single individual — even an 11-year-old boy — can make a difference. And in an age when personal advantage is the primary motivator and blase indifference rules, that’s a very important message, however formulaic the packaging.