Katherine Paterson's Newbery-winning Bridge to Terabithia has been a must-read for school kids since it came out 30 years ago.

A tale of two misfit fifth graders - a boy, Jess, and a girl, Leslie - who forge a deep friendship as they dream up a magical kingdom in the woods, the book addresses issues of bullydom, stressed parents, conformity-vs.-creativity, puppy ownership, death.

Yes, death.

Directed by Rugrats/Wild Thornberrys animator Gabor Csupo - it's his first live-action feature - Bridge to Terabithia is a faithful reworking of the novel, anchored by two solid performances: Josh Hutcherson (Zathura, Little Manhattan) as Jess, and AnnaSophia Robb (Because of Winn Dixie, Violet in Charlie and the Chocolate Factory) as Leslie. I note the young teen actors' credentials not just for reference's sake, however. There's an element of studio packaging about this project (seasoned kid stars, slick computer effects) that works against the grain of the story, that makes Jess and Leslie's spirited flights into imaginary realms seem a little less spirited, a little too mapped out.

But the movie - adapted from the book by screenwriters Jeff Stockwell (who trod similar thematic turf on The Dangerous Lives of Altar Boys) and David Paterson, the author's son - still manages to be emotionally compelling. Hutcherson plays a quiet, artistic boy who runs like the wind (in part to escape the noise and bad news permeating his household), and whose friendship with the sophisticated, mischievous new girl in town begins as a rivalry: Robb's Leslie runs like the wind, too. In fact, hers is the stronger wind - Jess beats all the other boys in a school race, but Leslie beats Jess.

And then, one day, they race each other to the end of a road, find an old rope tied to a tree, swing across the creek and - at Leslie's bright-eyed urging - start to explore the made-up land of Terabithia, with its evil creatures (tree trolls, giant furry rodent-things), its dragonfly warriors, its castles and cascading falls.

All of this, at first in quick glimpses and glimmers, is rendered by Weta - the band of digital wizards responsible for much of Peter Jackson's The Lord of the Rings.

But Terabithia is not Middle Earth (it's not even Narnia), and at times - especially in an elaborate end sequence - the giants, the knights, the birdcage maidens overwhelm. (This is the big difference between Terabithia and the like-themed, Oscar-nominated Pan's Labyrinth: Guillermo del Toro's R-rated, Spanish-language fairy tale also centers on a child's flight into fantasy, but the real world around her is depicted with equal vividness - the two universes are competing powers, one doesn't dominate the other.)

On the edge of Jess and Leslie's shared world are his dad, a hardworking hardware store clerk (Robert Patrick), a dour mom and a noisy brood of sisters, big and small. Leslie's parents, in a couple of brief scenes, come off as artsy, New Age twits - no wonder the daughter wants to flee to an imaginary place.

Also figuring significantly in Jess and Leslie's lives is Ms. Edmonds, a guitar-strumming music teacher with saucer eyes and a repertoire of baby-boomer chestnuts. Jess has a bit of a crush on Ms. Edmonds (Zooey Deschanel), who leads the class in boisterous sing-alongs - and leads Jess to an art museum on a fateful Saturday.

Bridge to Terabithia the movie, like the book, is buckets-of-tears sad. Director Csupo and company manage to get that - the simple power of a story about kindred souls, about loss, about the limitless possibilities of a lively mind - just right.

Contact movie critic Steven Rea at 215-854-5629 or srea@phillynews.com. Read his recent work at http://go.philly.com/stevenrea.