Griffins and goblins and trolls, oh my! (Not to mention ogres, fairies, imps and sylphs.) Mark Waters’ film, based on the popular series of children’s books by Tony DiTerlizzi and Holly Black, has them all, realized by the special effects team led by Tom Peitzman with an old-fashioned tackiness that seems positively charming in this age of ultra-glitzy CGI. “The Spiderwick Chronicles,” cobbled together from all five of the slender volumes in the series by a trio of scripters that rather incongruously includes John Sayles, could hardly be called a classic of enchantment, but it should certainly satisfy the eight-to-twelve target age group of the books while eliciting at least a bemused tolerance from any adults who accompany them. Teenagers, on the other hand, will probably consider it kids’ stuff, and children younger than six or so may find it just a little too scary for comfort.

The overarching theme is the importance of family bonds, even frayed ones. As the picture opens, mom Helen Grace (Mary-Louise Parker), separated from her husband, is moving with her three children to the remote old estate left her by her elderly—and, some say, deranged—Aunt Lucinda (Joan Plowright), who’s been deposited in a nursing home in town. The oldest of the siblings is commonsensical Mallory (Sarah Bolger), who has two brothers, studious Simon and troublemaker Jared (both played by Freddie Highmore). The latter is bitter over his parents’ separation and wants to live with his father in the city, not realizing his dad has gone off with another woman.

It isn’t long before the inquisitive Jared has found the secret study of his great-uncle Arthur (David Strathairn), who’d spent his life compiling a tell-all book revealing the secrets of the magical creatures that inhabit the area around the house, which the boy reads despite a warning that to do so will invite disaster. Soon he finds himself and the rest of his family threatened by the malevolent ogre Mulgarath (Nick Nolte), who orders his army of goblins and trolls to get the book, which will allow him to gain dominion over the world. Fortunately, the humans have some allies, the shape-shifting, honey-loving imp Thimbletack (Martin Short), whom Great-Uncle Arthur had enlisted to protect the volume, and the vengeance-seeking, bird-eating hobgoblin Hogsqueal (Seth Rogen), whose family Mulgarath wiped out. As it happens, Aunt Lucinda proves a help as well, and even Arthur, frozen in time by the sylphs, lends a hand.

Like so many movies nowadays, “The Spiderwick Chronicles” goes awry in the final act, with a goblin assault on the estate after Uncle Arthur’s protective circle of toadstools has been magically demolished that goes on far too long and involves entirely too much destruction. (With so many walls and ceilings destroyed in the process, you may be taken aback when the coda shows the house in pristine shape without a stick of furniture out of place.) But until that predictable miscalculation, the movie has a pleasantly modest tone, treating the story without condescension but at the same time not inflating it into quasi-mystical bombast along the lines of “The Golden Compass.” It’s actually fairly small-scaled and intimate, like a combination of old Disney fairy-tale and Ray Harryhausen mythic beast flick.

And the work of the human performers gives it considerable warmth. Whether it was really necessary for Highmore to play a dual role as both Jared and Simon is debatable, but he certainly proves equal to the task, differentiating the two nicely and giving them both winning personalities. Bolger makes a spunky, if somewhat brusque, older sister to the boys, and while Parker is a mite too wimpy as the mom, Plowright brings her usual fluttery regal demeanor to old Aunt Lucinda. Though one can imagine another actor bringing a greater sense of magical eccentricity to the fellow whose odd researches start all the trouble (and making more of his reunion scene with his now elderly daughter), Strathairn’s nervous timidity isn’t entirely out of place. And Andrew McCarthy’s performance as the faithless Grace father is mercifully brief. Among the other talent, Nolte appears only briefly in the flesh, as it were, and doesn’t make much of an impression even when reduced to a mere voice. But Rogen and Short prove real crowd-pleasers in their speak-only roles.

Setting aside the CGI effects, with their slightly homespun quality, the technical aspects of “The Spiderwick Chronicles” are all state-of-the-art, with veteran Caleb Deschanel’s cinematography predictably plush and the production design (by James Bissell) and art direction (supervised by Isabelle Guay) both excellent. Even James Horner’s score is better than his norm.

After so many failed attempts to fashion new “Harry Potter”-like franchises from children’s books—not just “The Golden Compass” but “Eragon” and “Lemony Snicket’s A Series of Unfortunate Events,” among others—it’s nice to encounter one that actually works, even if on a relatively modest level. Where “The Spiderwick Chronicles” might go from here is anyone’s guess (DiTerlizzi and Black will have to decide that in a new series of books), but at least this installment makes the transition to the screen smoothly and should have an especially long life on home DVD shelves.