The journey takes about an hour each way.
From his home to reach Cretin-Derham Hall, the storied high school on the west side of St. Paul that produced the likes of Joe Mauer, Chris Weinke, Steve Walsh and Michael Floyd, Cornell takes two buses.
It's about a 40-minute trip. He likes to arrive by 6 a.m., sometimes standing outside the doors of the school before they're unlocked.
When you've come as far as Cornell, a few treks across town offer little resistance.
"We like to say that God gives kids a lot of stuff," said Dan McQuillan, Cornell's position coach at Cretin-Derham Hall. "It's what they do with it that makes the difference."
Cornell, the No. 1-ranked prospect in the ESPN Junior 300, is doing plenty with his gifts.
He's added almost 30 pounds since the end of last season to his 6-foot-3 frame, reaching 245 as the Raiders open Thursday night against Roseville (Minn.) Area High School.
Cornell enjoyed a breakthrough offseason, advancing since February from zero scholarship offers to two dozen. Iowa was his first. Minnesota followed within minutes. His suitors today include Florida, Florida State, Michigan, Ohio State, Stanford and USC.
As the spotlight grows more intense, those close to Cornell say it's changed him none. The circumstances only strengthened his focus and forced him to recognize the challenges of this unique position; he's in a rare place, among the youngest prospects bestowed this label as the best in his class.
Yet Cornell's attitude belies his youth.
"Now," he said, "I have no choice but to work harder than the person across from me."
Cornell presents a case study in contrast. The truth about him is all a matter of perspective.
On paper, his high school career is halfway complete. Really, though, Cornell is just getting started.
He played less than a full season last year in his first at the varsity level. Ninth-graders don't suit up on varsity at Cretin-Derham Hall, and he suffered a broken ankle on the freshman team in 2011. In 2012, he fractured his hand but largely played through the injury.
"We knew the skill was there, but it didn't show on the field after the first few games," McQuillan said. "I do know this: If he shows up on your campus and you look at the body and how he runs, it doesn't take long to understand."
Such a scenario unfolded this year at USC. Cornell visited while on spring break. He met defensive line coach Ed Orgeron. One day later, the Trojans extended an offer.
ESPN's scouting report on Cornell awards him high marks for speed, explosiveness and physicality. While the report offers no direct comparisons, it says he shares traits with other recent top-rated players at his position.
You know the names: Robert Nkemdiche, Mario Edwards, Jadeveon Clowney, Da'Quan Bowers.
Cornell must live with the burden.
"He's in a spotlight that most of us can't imagine," Cretin-Derham Hall coach Mike Scanlan said. "I've always said it's like being Elvis. Everyone knows who you are. Everyone's looking at you. And they're all waiting to say you're not as good as people think."
Scanlan said he's never seen interest in a prospect escalate so quickly. He described it as an avalanche.
It could engulf a 16-year-old.
"I think he'll be fine," said Jashon's mother, Sheena Cornell. "I tell him not to let things get in his way. He's very strong-minded and very driven, so I don't have any worries about all of this interrupting him."
Cornell recalls Seantrel Henderson, the nation's No. 1-rated offensive tackle out of Cretin-Derham Hall in 2010.
Henderson sat at the center of a contentious recruiting battle. He signed with USC before the Trojans released him from his letter of intent, and he wound up at Miami.
A senior now, he's grown into an NFL prospect but never matched the hype from high school. Henderson endured surgery, a car accident, a suspension and the death of a close friend -- not to mention the specter of a lengthy NCAA investigation at his school and lofty expectations that stayed with him.
His story speaks to Cornell.
"You're guaranteed nothing," Cornell said. "I believe you have to earn everything in life. I've learned it's not all about being No. 1. You can come from anywhere, any position and go to any school. You've still got to work to get places."
Sheena gave birth to Jashon at age 15. In his early years, they lived on the troubled east side of St. Paul. It was difficult, Sheena said.
But feel no sympathy for Cornell. He is a product of that environment, molded by his experiences and the people he encountered.
Sheena's mother, Claudia Bynum, helped a great deal in those early years. Jashon's grandmother is from a family of 25 siblings. He met new cousins regularly on the playgrounds and streets of St. Paul, some of whom he never knew he was related to.
Cornell said his relationship with his father, Keeshon Parker, is "on and off." They talk. Parker recently moved to near his son's school.
"He wants to see me be successful in life," Cornell said.
Uncle Derek Cornell helped Jashon get into football. He looked up to Terrell Suggs, a family friend, Larry Fitzgerald, James Laurinaitis and others from the Twin Cities.
As a seventh-grader in public school, Cornell met Marcus Freeman, the former Notre Dame star as a tight end out of Cretin-Derham Hall. Freeman worked as a long-term substitute teacher in Cornell's English class.
They formed a quick connection.
"We see kids who are big," Freeman said. "Others are athletic. We saw something special in Jashon."
When Cornell moved to private school in eighth grade, Freeman went to work at Cretin-Derham Hall. He's now the dean of students and helps coach under Scanlan.
Freeman said he was right about Cornell from the start. The kid had something special. Credit his mother, Freeman said.
Sheena has three daughters younger than Jashon. She remains proud of their victories over the past 17 years, smiling as she watches her son handle an interview this month at a downtown Minneapolis restaurant.
"I will sacrifice and do anything for my kids," she said. "I'm a very hard worker, so I can say he got that from me."
Cornell is just starting to narrow his college favorites. Remember, he's not 17 until Dec. 30.
Still, he feels pressure from all sides. Receiver George Campbell (Tarpon Springs, Fla./East Lake) and running back Damian Harris (Berea, Ky./Madison Southern), 2015 prospects committed to Michigan, communicate with him. Guess where they want him to go.
College coaches promise a pipeline to the NFL.
"He has no obligation to anybody else," said Scanlan, the Cretin-Derham Hall coach. "He doesn't owe anybody anything."
He hears talk about Notre Dame, the choice of former Cretin-Derham Hall standouts Freeman, Floyd, Rashon Powers-Neal, James Onwualu and others.
Minnesota is a popular suggestion, too. Cornell said the Gophers are a "real contender."
So many people, it seems, know what's best for him.
"Some of the stuff people are saying might be nonsense," he said, "but you've got to get used to it all."
Cornell has grown close over the past year with Broderick Binns, recruited out of Cretin-Derham Hall to Iowa, where he earned second-team All-Big Ten honors in 2011.
Binns trains with Cornell. He's seen the kid's dedication and heard about the long bus rides.
"Stay with people you trust," Binns said, "the people who been there for you. He's going to have all kinds of people telling him different things, but he needs to listen to the people who got him here."