For this 12-year-old, the youngest student ever to attend FIU, college is a long-awaited challenge and a daily adventure.

"We have fun here," he said as he prepared to start a work sheet on pistons, gases, and pressure with his lab partners.

Welcome to the world of Sky, who is taking a full course load of physics, calculus, and Chinese language classes at the university _ and still finds time to play pool and table tennis in the game room at the West Miami-Dade, Fla., campus.

A home-schooler who has a third-degree black belt in tae kwon do and is fluent in Korean, he is dual enrolled and officially finishing high school at the end of this semester.

When he starts classes in the fall as a full-fledged college student, he'll have as many credits as a sophomore.

The Pembroke Pines, Fla., preteen, who is classified as "profoundly gifted," started taking classes there when he was 10.

"I felt really, really small," he said.

But Sky, whose given name is Sebastian Hanul Choi (his father is Korean, and his middle name means "Sky" in that language), says college is a good fit _ even though he has to rely on rides from adults to get to and from campus.

Middle school, he said, "would be painful. It just wouldn't be any challenge."

"He's really happy," said his mother, Dana Choi. "It's made it so much easier because I know he's being challenged, I know he has room to grow."

EARLY INDICATIONS

She always knew her son wasn't average.

When he was 3, he asked to leave a party so he could finish a math workbook.

Then there was the time he memorized the multiplication tables in one day.

When he was 4.

When he started fifth grade, Sky's parents pulled him out of private school, where he had already skipped a couple of grades, and home-schooled him. He took classes online, used home-school curriculum, and went to Sunshine Learning Center in Margate, Fla., which caters to home-schoolers, for some high school-level classes.

"When you have an 8-year-old begging you to go to college, you wonder: How could that be?" his mother said.

And when Choi, an attorney with Miami's Holland & Knight law firm, learned that Sky could pursue dual enrollment with a university in Miami-Dade even though the family lived in Broward, Fla., she met with a representative from FIU and handed in Sky's test scores.

He took his first class _ Chinese language _ at 10. The next semester was Chinese and pre-calculus. He added more the following semester, and now he's taking 14 credits. His GPA is 3.83.

Before Sky took an introductory physics seminar this semester, he e-mailed this to the professors: "It seems like I've been waiting a long time to finally get to study physics in depth. As you can imagine, it's not easy to get the necessary math courses and high school science courses when your age is in the single digits."

SENSE OF HUMOR

"That's the one that stopped me," said Caroline Simpson, associate professor in the department of physics.

Simpson said Sky introduced himself like this before giving one presentation in the course: "Hi, I'm Sky. I'm 12."

"And the whole room just cracked up," Simpson said. "That's kind of his attitude. He doesn't have any problem with it."

His professors and classmates don't appear to have any problem with it either.

"He's actually pretty popular in our school," said Alex Brieto, 20, one of Sky's lab partners. "I mean, when have you seen a 12-year-old kid in college?"

George Walker is a theoretical physicist who serves as dean of the university's graduate school and senior vice president for research development and graduate education.

He said he has seen many talented young scholars in his more than 50 years in the field.

"But I have not seen any that would exceed the promise and the interest that Sky has at this stage," Walker said.

'INSATIABLE NEED'

Students who are profoundly gifted are known to learn at a rapid pace and understand complex ideas at an early age. They fall in the 99.9th percentile or higher on standardized and IQ tests.

The Davidson Institute for Talent Development, which serves those youths, has 1,400 "Young Scholars" between the ages of 5 and 18 around the country, including Sky.

Although the institute doesn't track the number of young teens or preteens in college, it estimates that approximately a quarter of the students in the Young Scholars program take college courses.

"They just have this insatiable need for constant mental stimulation," said Jill Adrian, the institute's director of family services. "Which can make it tricky as a parent and an educator of these students."

'COMFORTING'

Sky plans to graduate from FIU with a ...