AUDUBON, N.J. — Back in the spring of 2003, long before Joe Flacco was a Super Bowl-bound quarterback, he was a high school senior on his class trip to All-Star Sports in Disney World.

A group of students gathered on the football field.

“Joe, of course, had a football in his hands,” said Betsy Kirkbride, who teaches marketing at Audubon High and was one of the chaperones on the trip. “Other boys start gathering from other schools, other states. So we say to the other kids, ‘Want to see something?’ ”

The bait was on the hook.

“Joe rolls his eyes, looking at us, humoring us, two chaperones looking for bragging rights,” Kirkbride said with a smile. “Joe doesn’t say a word and throws the football 70 yards … straight through the uprights.

“One step; tight spiral. The other kids are just standing there, saying, ‘Who is this?’ ”

This is Super Joe Flacco.

The football world is beginning to understand what they always knew about Joe Flacco in this small South Jersey town, near Philadelphia. The Ravens quarterback has a golden arm and a perfect, unflappable winning makeup that critics still don’t understand.

Flacco acts the way an NFL quarterback should act. He has taken his Ravens to Super Bowl XLVII in New Orleans to face the mighty 49ers. Along the way, he has beaten two quarterback legends in Peyton Manning and Tom Brady at their football homes.

“I like to tell people, look, man, we raised him to be a CEO, not a carnival act,” Joe’s father Steve said of Joe’s disposition. “You’re a quarterback, why would you want anybody ever see you sweat? And when you throw a touchdown pass, act like you’ve done it before.”

On the field, Joe Flacco is CEO of the Ravens’ offense. Cool, calm and collected. You could say he is unflaccable.

“We laugh because people don’t like Joe’s disposition. Well, we love his disposition. We’re responsible for it,” Steve said of how he and his wife Karen raised Joe. “You always want to carry yourself with class and dignity. You never want to get upset. We don’t like it when teammates yell at each other on the field.

“If you’re angry, that shows you’re melting down.”

Talk to Steve Flacco for five minutes, and his passion for football explodes. He is a graduate of the University of Pennsylvania Wharton School and played football and baseball at Penn. Karen was an excellent athlete as well. Joe is the oldest of six children in this athletic family. His brother Mike is a first baseman in the Orioles organization. Joe’s youngest brother Tom is a quarterback at Eastern High in Voorhees and is expected to be a Division 1 quarterback.

Joe, 28, is gifted with size (6-foot-6, 232 pounds) as well as that golden arm.

“I never dreamed Joe would be as big as he is,” his dad said. “I’m 5-11; my wife is 5-6. If you shake his hand, his right-hand is Godzilla-like. He never really lifted weights. That’s all from throwing a football.

“Physically, there is nobody who throws the football better than he does, and his height helps because under center he is looking through those guys’ helmets and not their backs and shoulder pads. Height helps in terms of vision, and vision is probably 90 percent of what they do.”

Steve said this season has been a dream come true.

“We’re so happy for the fans in Baltimore,” he said.

The Flacco family tree stems from football. Joe’s grandfathers not only were high school football teammates at Camden Catholic, his grandfather Joe (known in the family as “The Original Joe Flacco’’) was an end who caught passes from Joe’s mom’s dad, quarterback Tom Madden. They graduated in 1954.

“I keep telling Joe when you see John Madden you have to tell him you are related,” Steve said with a chuckle.

As for that long pass trick, Steve would take Joe to the football field and from 50 yards away have Joe aim at the crossbar and the uprights.

“Sometimes Joe would hit them three out of five from that distance,” Steve said.

For the first three years of high school, Flacco was coached by Mark Deal, who remains a close family friend and will be traveling to New Orleans with his wife Paula along with the Flacco contingent, including all the grandparents.

In Flacco’s senior season, Deal moved to coach Gateway Regional High because budget cuts eliminated his in-school job at Audubon. That year, before the game between Audubon and Gateway, the coach and his former quarterback were having a friendly chat at the 50-yard line when Flacco pointed to the flag at the top of the right upright, a la Babe Ruth, and said, “Watch this coach.”

“Now, remember, he’s 50 yards away, the end zone is another 10 yards and it’s the top of the upright, about a 75-yard throw,’’ Deal said, still amazed at the memory. “Joe took one step, threw it, and darned if he didn’t hit the top right upright.”

Now you know why Flacco was able to throw that 70-yard strike to Jacoby Jones so easily over the heads of Broncos defenders in the final seconds of regulation in the Ravens’ stunning double-overtime Divisional round upset in Denver.

In his senior season at Audubon, Ralph Schiavo coached Flacco and let the football fly. Flacco still holds the South Jersey record for passing attempts (55) and yards (471) in a game. He was the tidal wave in the Green Wave, but he was much more than the star player.

“He had a calming effect on everybody,” Schiavo said. “When we’d call a timeout, Joe would have three or four intelligent suggestions.”

Flacco is the only quarterback in NFL history to win a postseason game in each of his first five seasons and is regarded as the best deep thrower in the game.

“He’s such a competitive guy, very fiery inside,” said Deal, who attended the playoff win over the Colts then went back to Flacco’s house after the game. “Joe was talking about the plays he didn’t make, not all the plays he made. That’s what he is all about. That’s how he gets better. It’s unbelievable to me that some people don’t believe he’s an elite quarterback. I think that bothers him a little bit.”

Flacco has thrown eight touchdowns this postseason with zero interceptions.

“If that’s not elite, I don’t know what is,” Deal said, also pointing to those five straight years of postseason victories.

Since coming into the NFL in 2008, no quarterback has won more games than Flacco.

Every summer Flacco comes back to speak at Deal’s football camp.

“He hasn’t forgotten where he has come from,” said Deal, now the coach at Clearview Regional High School.

Family and friends go to every home game in Baltimore. They used to go to out to dinner as a group (as Joe would patiently sign autographs for fans). After Joe and his wife Dana, whom he started dating his senior year at Audubon High, had their first child, Steve, named in honor of Joe’s dad, this past June, the dinners now take place at their house.

“Joe is really a super guy, and his family are all such good, decent people,” Paula Deal said.

Noted Steve with fatherly pride: “Joe’s a great kid. All our kids are great kids. We’re so fortunate.”

There is a playful side to Joe, too. At one of those postgame dinners, Flacco and tight end Dennis Pitta, Joe’s close friend, egged on one of Joe’s younger brothers with a small financial incentive to eat as many éclairs as he could before getting sick to his stomach.

Yes, brothers always will be brothers, even if one is an elite NFL quarterback.

Speak to the teachers and administrators at Audubon High and this is what you hear about Joe: quiet, dependable, self-confident. Flacco excelled in three sports: football, baseball and basketball.

Gregg Francis has taught history for 36 years and was impressed by Flacco.

“Joe was an excellent student,” Francis said. “I used to call him ‘Biceps’ because he was skinny at the time. He’s a proud kid, who was a great athlete. He had the size and the speed. He could have been a major league baseball player, too.”

Superintendent of Schools Don Borden was the principal of Audubon when Joe attended the school.

“Joe is the same kid that you see on TV, unflappable,” Borden explained. “I remember one time a kid threw something in the cafeteria, trying to get something started, and it went right past Joe and Joe looked over at the kid, like, ‘What the heck are you doing?’ Joe didn’t react at all, whereas another kid might have flipped out.”

Then came these special words from Borden: “Joe is the kind of kid you hope your kid grows up to be.’’

Flacco played safety, too, in high school. His dad taught him to use his long arms to horse-collar opponents, which you could get away with back then.

“We used to call him the ‘Long Arm of the Law,’ ” Steve said. “He’d yank them out of their shoes.”

Drive through town and you see purple Ravens flags flying from front porches.

“This town is going to be crazy through these next two weeks,” Schiavo said.

Joe Flacco is beloved here, and Betsy Kirkbride remains one of Joe’s biggest fans.

“I wish they would give him the props he deserves,” she said.

When Flacco was drafted by the Ravens she immediately called the NFL and ordered a Ravens’ jersey. The sales person said, “He hasn’t even picked his number.”

“He’ll be No. 5,” Betsy said.

No. 5 was Joe’s number at Audubon.

When you watch this Super Bowl, and if there are any casual fans around, repeat the words Betsy Kirkbride said to those students standing on that football field nearly 10 years ago in Florida.

Want to see something?

Watch Super Joe Flacco throw that football.

kevin.kernan@nypost.com