“Going to a local high school game is, you know, I don’t think is a problem,” Sullivan said. He declined further comment.

A Venerable School

Turned Powerhouse

With its looming oak trees, elegant brick buildings and a history dating to 1845, the campus of Tilton School exudes the serenity of Norman Rockwell’s New England. But the last few months have been anything but tranquil for Tilton, which has a reputation for sending students to well-regarded universities in the Northeast and elsewhere.

Tilton has also become a national power in basketball, and Chris Driscoll is one of the people most responsible. Seven players on Tilton’s roster this season are from B.A.B.C. and he had steered several prominent players there in previous years.

For a time, the relationship between Tilton and Driscoll was mutually beneficial. The players that Driscoll steered to Tilton used their time at the school to qualify academically so they could play for the colleges of their choice. They also helped Tilton become an increasingly powerful basketball school nationally. Before, Tilton had been a middling performer on the prep school level. Now, while still mainly playing other schools in New England, Tilton has become a recognized team around the country.

It was not until Noel arrived that O’Neil, Tilton’s coach, and others at the school began to feel uncomfortable with the association.

Noel originally entered Tilton to repeat his sophomore year. (He had cracked a growth plate in his knee while warming up for a game with Everett.) After his knee healed and he became a coveted prospect, Noel decided to try to graduate from Tilton this year instead of in 2013. Tilton was annoyed by the decision, but Noel stuck to it and remained at the school for what will be his final high school season.

For his part, Driscoll is no longer welcome at the school.

Tilton’s headmaster, Jim Clements, declined to comment directly on Driscoll, whose son, Jeremy, attended Tilton as a postgraduate. But he did say it was his first time in his 14 years on campus that he had barred anyone from the school because of a relationship to an athlete. Still, Driscoll has maintained contact with Noel and acted as a liaison to college recruiters and some members of the news media about his recruitment.