THE set of “The Adventures of Sharkboy and Lavagirl in 3-D,” opening Friday, was overrun with kids, which is exactly the way director Robert Rodriguez (“Spy Kids”) likes it.

Although his last movie was the sultry R-rated comic book adaptation “Sin City,” Rodriguez says that it was great working with kids again, since it “brings out the kid in everybody, even the adults.”

“Sharkboy and Lavagirl” follows the adventures of 10-year-old outcast Max (Cayden Boyd) and the titular superheroes’ attempts at saving the fantasy world Planet Drool – where it’s so cool, it makes you drool – from the nefarious clutches of Mr. Electric (George Lopez).

Meet the film’s two Taylors (who went by “Sharky” and “Lava” on set to avoid confusion) and the younger Rodriguez that made the multi-dimensional family movie possible.

SHARKBOY

Taylor Lautner

Boys will be boys – even if they’re half-shark.

“I mainly liked the scenes where we got to get dirty and that involved food,” says 13-year-old Lautner, who plays the shark/boy hybrid character that shoots water out of his hands and goes into a “shark frenzy” when angry.

“My favorite scene in the movie was probably when my boot gets caught in the chocolate-chip cookie, and I lick the chocolate. That was a lot of fun because we had to do that take a lot, and we all got to eat the chocolate.”

A hip-hop dancer and athlete, the Grand Rapids, Mich., native also holds four junior world martial arts titles, so all those flips and extreme moves used to beat back the electricity chords were all real.

“Robert [Rodriguez] didn’t know about my martial arts before he booked me, but when we were shooting, I was messing around doing flips and he found out about it,” Lautner says.

“He asked me to choreograph my own fight scene in the film, and I was like, ‘Sure, yeah!’ So he set up some mats for me and had me do my own fight scene.”

LAVAGIRL

Taylor Dooley

It’s impossible to miss the bright pink hair – it even outshines Dooley’s pink unisuit with molten lava running through it.

Off the set, “other moms would give my mom the dirtiest looks, like ‘What are you doing to your kid?’ but teenagers would come up and say, ‘That’s so cool! My mom would never let me do that!” she laughs.

“I loved having pink hair, I’d do it again any day, even though it ruined my hair. I can’t go into the pool or dye it again, otherwise my hair will fall out,” says Dooley, who is now back to her natural brown hair.

What the 12-year-old actress and model – this is her first feature film – liked most about Lavagirl, was that she’s not the traditional kick-butt female superhero.

“I love how Lavagirl is so girly-girl,” says the Gross Pointe, Mich., native. “I’ve always wanted to be a superhero, but I’m not really that tough – you can ask Taylor [Lautner], he laughs when he sees me try to punch,” Dooley says.

“When I picture a [female] superhero, they’re just not girly-girl, you know? So it was really fun to play a character that’s a girly-girl superhero.”

THE WRITER

Racer Max Rodriguez

Sure, Robert Rodriguez directed, wrote, filmed, composed and edited the movie, but the real genius behind “Sharkboy and Lavagirl” is actually his son, Racer Max.

The superheroes, villain and Planet Drool came out of the 7-year-old’s imagination and drawings.

“We were in the swimming pool one day, and Racer said, ‘Yeah! Sharkboy! Let’s make a movie about Sharkboy – I’ll be Sharkboy!'” says Rodriguez, who decided to help Racer draw a children’s book for his brothers based on the character instead.

“I wanted to show him how one idea led to another, so I told him to create a girl character, and he came up with Lavagirl. Then I was like, ‘This is kind of a cool idea,'” says Rodriguez.

“When the studio called and said they wanted another 3-D family movie and I didn’t have any ideas, I said, ‘What about Sharkboy and Lavagirl?’ They said, “That sounds fantastic,” and Racer and I started putting it together.”

Ultimately, Racer, who received a writing credit on the film, was drawn to sharks because his dad brings back footage from his shark dives. The attraction to lava is another story.

“I like lava because we play lava – we put pillows on the ground, and the pillows are rocks and the ground is lava, and my dad’s the lava monster,” Racer says.