Nicknamed after a pudgy animated panda, Giants third baseman Pablo Sandoval kicked off a campaign Wednesday to promote physical fitness to schoolchildren.

Yep, insert joke here.

Sandoval, the 260-pound or so ballplayer, has taken heat for his girth in recent months and might seem an unlikely choice to preach the gospel of healthy living.

Yet, there's no arguing that the chunky 23-year-old can field a screaming grounder on a bad hop for an out or hit a baseball going 90 mph over a fence 400 feet away.

Also noteworthy: Television adds 10 pounds and those cream-colored pants do little to flatter a figure.

But perhaps most importantly, kids love Panda.

Sandoval kicked off "Operation Panda" at the Mission Education Center, a public elementary school for recent Spanish-speaking immigrants, a new Giants program named after Sandoval's offseason effort to drop a few pounds.

Wide-eyed students asked him about his favorite fruit (bananas), his favorite exercise (jogging) and other pertinent questions.

"Do you have a mascot?" 5-year-old Edwin Olivares asked.

Sandoval laughed.

"I'm my own mascot," he said. "I'm a panda."

The power hitter, affectionately nicknamed Kung Fu Panda by his teammates, told the 140 or so assembled students to eat fruit instead of candy, drink lots of water, read at night before bed, get plenty of rest and listen to their parents.

"I'm a normal person like you guys," the native Venezuelan told the children in Spanish. "It's not easy to get to this level, but you have to work hard to get to your dreams."

A chaotic game of Wiffle Ball followed the question-and-answer session, with Sandoval playing pitcher.

That's when Sandoval broke out his trademark smile, laughing as he called kids back to the plate on a foul ball.

Batting practice came next. As students hit off orange pylons acting as tees, Panda took a hot shot off his chest.

"Ow!" he said rubbing the injury, his game-ready reflexes apparently absent on the black top.

Sandoval was especially impressed with 9-year-old Merlin Dominguez, who launched one over the chain-link fence maybe 30 feet away.

"Let's see that again," he said, teeing up another plastic ball.

The second blast also cleared the fence. It was hard to tell whose smile was wider: Merlin's or Panda's.

"We could use her on the team," Sandoval said. "I should get (Giants General Manager Brian) Sabean to hire her."

For a few minutes more, Sandoval watched the students take monster swings that spun them around and dropped them on the ground as he recounted what he was like as a child.

"Definitely" a troublemaker, he said.

He pointed to the scar below his left eye. At age 1, he hit his dog with a bat when the animal took his ball. The dog bit him. The next day, he hit the dog again and he got bit again - this time on his back end. There's a scar there too, he said grinning.

As the 90-minute visit came to an end and he prepared to leave, he was swarmed by kindergartner hugs.

Sandoval will probably visit at least a couple more schools before summer break, team officials said. That appeared to be just fine with Panda.

"Being out here reminded me of how much I love ... being with kids," he told the students. "This was a gift to me."

E-mail Jill Tucker at jtucker@sfchronicle.com.

This article appeared on page C - 1 of the San Francisco Chronicle