"What's a nice Catholic boy from New York doing at a fundamentalist university in Virginia?"

Education Secretary William J. Bennett's opening line showed the cabinet officer was ready for any critics here at the Rev. Jerry Falwell's Liberty University.

But inside the corrugated metal gymnasium atop Liberty Mountain, Bennett found a ready audience today for his message that America has stopped caring enough for its children.

He received a standing ovation from the 7,000 students, faculty and visiting pastors who heard him proclaim that schools must teach moral values and that parental love -- not social programs -- is the key to adolescent success.

The "most critical determinant of adolescent well-being is the bond between parent and child," Bennett said, to hearty "amens" from the audience.

It was the education secretary's first visit to Liberty, where emphasis on the Christian life includes mandatory chapel thrice weekly and strict prohibitions against smoking, drinking and rock music.

Although some students said they were surprised by Bennett's opening statement that he is a Roman Catholic, many rated him one of the school's best speakers.

"We have a lot of speakers from Washington," said Shelly Scholes, 20, a junior. What she liked about Bennett, she said, was that he "was not from D.C. with a lot of big words."

"I was shocked that he said he was Catholic -- that he just came out and said it," said junior Jaime Strohecker, 21, of Harrisburg, Pa. "Yet I was really impressed with his moral views. I was impressed that he seemed so family-oriented."

Several students said they agreed with Bennett's warning about the decline of American family life. "My mom's a teacher, and probably three of her students come from a real family," said Inger Welms, 21, a senior from San Diego.

Senior Derek Towse, 21, of Sharon Springs, N.Y., said he was pleased that Bennett "seemed very moral. He spoke out against abortion. He seemed very conservative."

Falwell, the television evangelist who founded the college 15 years ago, introduced Bennett and joined in praising his speech. But the minister sidestepped a question about whether the Reagan administration is moving fast enough for social change. That, Falwell said, "is something we have to do . . . at the grass roots."

After his quip about his presence at Liberty, Bennett noted that he visited the University of Notre Dame's Catholic students last year and plans to visit Yeshiva University's Jewish students next year. Being religious, he said, is not incompatible with being an intellectual.

Bennett focused much of his talk on his contention that the two decades of social programs that began in the 1960s helped some children, but not children overall. He cited declining College Board scores, increasing numbers of out-of-wedlock births and growing drug use among young people.

Colleges and universities must prepare students not only for jobs, but also for "the care, nurture and protection of children" as they become parents.

Bennett said later he did not mean that universities should offer "a major in parent studies or classes in changing diapers," but that "faculty members should act as role models in what it means to care for the young."

Students at Liberty have heard a number of famous speakers. Recent visitors to the 4,000-acre campus have included Vice President George Bush, Transportation Secretary Elizabeth H. Dole and her husband, Sen. Robert Dole (R-Kan.), Sen. Edward M. Kennedy (D-Mass.) and Rep. Jack Kemp (R-N.Y.). Most have come at Falwell's personal invitation.

"God bless you, Mr. Secretary," said Falwell as Bennett left the lectern.

Bennett returned to Washington in one of the university's executive aircraft. He paid the school the commercial fare to Lynchburg for the flight, a spokesman said.