THE KIDS at school call Sam Reid Jr. "The Hulk" or "Hercules." And one look at his sinewy, 6-2, 235-pound frame and you'll know why.

However, when the Central High senior completed his final throw in the shot put at yesterday's Penn Relays, a familiar voice rang out and bestowed another moniker.

"That's my sister's 10-pound baby!" shouted Lasandra Cobb, a very proud aunt.

"Oh, yeah," Reid said later with a sheepish grin, "I was big when I came out. I was a 10-pound baby."

Whatever you call him, his name is going into the Lancers' record book. On his second-to-last attempt, Reid Jr. threw 17.81 meters (58 feet, 5 1/4 inches), breaking Geoffrey Seay's school record of 17.77 meters (58 feet, 3 inches) in 1981. Reid already owned the school's indoor record of 17.53 meters (57 feet, 5 inches), and yesterday's toss also earned fifth-place and a medal.

Benjamin Bonhurst, of Smithtown (N.Y.) West High, won the event with a throw of 19.33 meters. Andrew Robinson, from McDonogh School in Owings Mills, Md., finished second at 18.16, while Corey Murphy (18.13), of Longwood (N.Y.), and Jason Bryan (17.85), of Rumson-Fair Haven (N.J.) finished third and fourth, respectively.

"Geoffrey Seay had that record for a long time, so for me to beat it, it feels good," Reid said. "Hopefully, nobody else can beat it now.

"I wanted it. It's in the hallway in our school. All the records are there, and I just kept looking at it, like, 'I gotta beat that. I have to hit it and if I don't, I'm gonna hate myself.' "

No need for self-loathing on this or any other day. The Mount Airy resident carries a 3.76 GPA and is contemplating engineering, physics or computer science for college. He was also a 4-year starter on the Lancers football squad (playing both offensive and defensive lines) and was a Daily News third-team All-City selection last season.

Track-and-field suitors from Monmouth, East Stroudsburg, Morgan State and Adams State in Colorado were in attendance. Reid said he'd love to play both sports, but it looks like only track and field right now.

"He's a great kid, works very hard and is very focused," Central track coach Fred McCray Jr. said. "I can't take the credit. You have to give it up to [assistants] Arnie Shiffrin and Barry Swanson. They really work with him and I'm just here to be a cheerleader."

No shortage of those yesterday.

You already met Aunt Sandy, who was there with another aunt, Michelle. Mom and Dad, Stephanie and Sam Reid Sr., were also in attendance, as was Sam's older sister Charlene and grandmother Vera, who was celebrating her 69th birthday. Shiffrin was the school's longtime indoor track coach, whom McCray Jr. called a "pioneer" in Central's track program. Reid sought Swanson's counsel between throws.

"It's very special," Reid Jr. said. "I didn't think I would make finals, truthfully."

"I got to come in fifth in the Penn Relays, one of the biggest track-and-field events in the country, so that's pretty decent."