Visually ambitious and riotously energetic but burdened with a storyline that’s a weird medley of irritating characters and strange messages, “Wonder Park” ends up as just another mediocre computer-animated children’s movie. It comes from the Nickelodeon network, and should have stayed there.

The picture’s petite protagonist is Cameron Bailey (voiced by Brianna Denski), who’s constantly called “June Bug” by her mom and dad (Jennifer Garner and Matthew Broderick—his character’s name is not given as George, but he’s such a selfless sweetheart it might as well be). June has been encouraged since she was but a babe to use her imagination, and the message certainly took—now a tyke of nine or ten, she’s constructed a magical amusement park out of her dreams.

June’s Wonder Park is a collection of “splendiferous” rides and attractions, which June adds to by communicating her ideas to its creative director, a chimp named Peanut (Norbert Leo Butz), a stand-in for her beloved plush toy. Other animals keep the place running for its huge crowds: a practical-minded wild boar named Greta (Mila Kunis) and her porcupine buddy Steve (John Oliver); a pair of goofy beavers, Gus (Kenan Thompson) and Cooper (Ken Jeong); and Boomer (Ken Hudson Campbell), a wacky blue bear with a habit of going into hibernation mode on a dime.

But June isn’t content with just imagining her park. A pushy, aggressive sort, she enlists the neighborhood kids, including her subservient pal Banky (Oev Michael Urbas), to help her build an actual thrill ride, assembled from bits and pieces of stuff—like fence posts ripped from other people’s yards and even road signs (what happens at the intersection where the “Stop” sign was removed is, happily, never shown). The inaugural spin, of course, is a NASCAR-level action scene.

June’s energetic fun is, however, cruelly interrupted when her mother falls ill and has to go off for treatment for her undisclosed ailment. Thrown deep in the doldrums, she abandons her imaginative pursuits until her father insists that she go to math camp with her friends. She suddenly decides her dad can’t get along without her, and makes poor Banky fake illness to stop the bus in mid-journey. Wandering into the forest, she stumbles into Wonder Park, now derelict because of her neglect. (For some reason it’s been taken over by hordes of zombified little monkeys.) Naturally she must rediscover her sense of purpose to join with her animal friends to restore it to its former glory and get home, where good news, needless to say, awaits her.

There’s nothing wrong with encouraging kids to have dreams and hold onto them, of course, but “Wonder Park” pushes the message way too hard, turning June into a really annoying child. Worse, the place she’s created isn’t terribly interesting—a ride made of glow sticks is supposed to wow us, and she seems obsessed with roller coasters that push ahead at remarkably dangerous speeds.

Nor are the animal characters that run the place especially winning: Peanut is a particularly boring sort, and Greta isn’t far behind, while Boomer, Cooper and Gus are overbearing (expectedly, with Jeong among the voice actors); only Oliver’s laid-back porcupine is somewhat amusing. As to the other human characters, June’s parents are simply dull, while Banky is a poor man’s Milhouse Van Houten.

To be sure, kids ten and under might enjoy the movie: despite the mom-in-jeopardy part of the plot, it’s generally colorful and moves pretty quickly, and they might find June agreeably spunky rather than grating. Older kids and adults, on the other hand, will probably find it a chore to sit through, despite its professional sheen.

Though not targeted at an older crowd, though, “Wonder Park” could find an audience among college-age keg-lovers who could use it for one of their drinking games. The word “splendiferous” occurs so frequently in the script that if all uses of it were erased, the movie would shed a goodly portion of its running-time. So if one had to chug every time it’s spoken, you’d probably be sloshed after thirty minutes or so. That’s not a recommendation, just an observation.

One historical footnote: the picture’s original director, Dylan Brown, was removed from the project last year after charges of harassment were leveled against him. He was reportedly replaced by David Feiss, Robert Iscove and Clare Kilner; but in the end no director is credited. This hardly rivals the Bryan Singer-“Bohemian Rhapsody” situation, but it’s yet another example of what’s become SOP in today’s Hollywood.