In its efforts to crack down on secondary schools that give quick and easy grades to high-profile athletes, the N.C.A.A. has drawn up an initial list of 15 schools from which it will no longer accept transcripts.

The N.C.A.A.'s plan was outlined in a document that was e-mailed to colleges across the country over the weekend. The list of so-called invalid schools will be made final by July 1. This would allow students who have attended schools under review to know if they could enroll in college this fall.

"That's the first list of subsequent lists," said Kevin Lennon, a vice president of the National Collegiate Athletic Association. "More to come, is the way I would look at it."

None of the 15 schools are regarded as an athletic powerhouse.

One of the schools on the list was University High School in Miami, which closed in December in the wake of an investigation by The New York Times that revealed it gave easy grades to high-profile athletes.

Also on the list were Celestial Prep in Philadelphia and Philadelphia Christian School, two schools attended by the former George Washington University star Omar Williams, who graduated from the university this spring. Williams's questionable academic record in high school drew scrutiny from George Washington's faculty senate.

A number of schools that have come under scrutiny for their questionable academic standards were not on the initial list. Lennon said that N.C.A.A. staff members had visited at least seven schools and that they were currently on the road visiting other questionable schools.

Lennon confirmed that Lutheran Christian Academy in Philadelphia was one of the schools the N.C.A.A. had visited. Lutheran Christian is coached by Darryl Schofield, the former coach at Celestial Prep and Philadelphia Christian School.

In an article in The Times in February, four former Lutheran Christian players were quoted as saying that they were not required to attend classes and that their only teacher was Schofield. In an article in The Philadelphia Inquirer yesterday, Schofield called the publicity surrounding his school and the N.C.A.A. investigation "a public lynching." Reached on his cellphone last night, Schofield hung up and did not respond.

The e-mailed document also noted that the N.C.A.A. could deny a transcript from schools not on the invalid list. The N.C.A.A. has given its clearinghouse the authority to deny transcripts that reflect questionable jumps in grade point average.