If you parents out there objected to the violence in "The Karate Kid," "Teenage Mutant Ninja Turtles" and/or "Home Alone," you might want to steer your kids clear of "3 Ninjas."

But if you're among those who found those movies to be harmless, cartoonish fun, consider "3 Ninjas" in the same league. In fact, consider it a clone.

The story, which is little more than an outline for three big set pieces, has three young brothers (Michael Treanor, Max Elliott Slade, Chad Power) learning "the ninja ways" from their aging, but very nimble grandfather (Victor Wong).

There's a subplot about the kids' workaholic dad, an FBI agent, objecting to his kids' learning martial arts as he virtually ignores his family. (Guess what life lesson he'll learn by the film's end?) And the boys have a run-in with the school bullies.

But most of the film has to do with an evil gunrunner (Rand Kingsley), who plots to kidnap the kids so their father will leave him alone. To complicate matters, the villain was trained in his youth by Grandpa.

The first set-piece is the opening, as the boys are trained by their grandfather and eventually meet up with Kingsley and his henchmen for the first time. The second comes when three goofballs, who talk in Waynespeak (as in "Wayne's World"), attempt to kidnap the boys from their beds and are foiled a la "Home Alone." The third is the climactic showdown aboard a docked freighter, culminating with a one-on-one battle between Grandpa and the bad guy.

These three big fight sequences are punctuated with cartoon sound effects and lots of comical variations on beating people up, to soften the effect of the violence, which, on the whole, resembles a Tom and Jerry cartoon.

For me, "3 Ninjas" had its amusing moments but was also tedious at times. For the kids who surrounded me it was terrific — they laughed, hooted and cheered the three young heroes, with whom they obviously identified.

One quibble: How come, with their maternal grandfather being Japanese, none of these boys shows the slightest physical Asian trait? For that matter, neither does their mother. Was it really necessary to cast Mom and the kids as WASPs?

The film is rated PG for considerable bloodless violence (and the disturbing image of a gun being put to a child's head), along with some mild vulgarity, such as the expected kicks in the crotch and a scene where the kidnappers suffer from diarrhea.

— "PETAL TO THE METAL" is a nice surprise, a short, G-rated cartoon that precedes "3 Ninjas." While the animation isn't up to Disney's usual standard, it's an amusing romp with a new character, a cat named Bonkers. Here, he's a delivery boy for a flower shop trying to get to a movie star's apartment by the appointed time.

"Petal to the Metal" isn't up to the "Roger Rabbit" shorts, but it's still fun. And let's encourage this trend of including cartoons before features.