The class valedictorian was booed and another student was applauded for holding a moment of silence after a judge barred prayer at Washington Community High School's graduation.

A federal judge issued a restraining order days before Sunday's ceremony blocking any student-led prayer. It was the first time in the 80-year history of the school in this Peoria suburb that no graduation prayers were said.

Valedictorian Natasha Appenheimer was booed when she received her diploma. Her family, backed by the American Civil Liberties Union, had filed the lawsuit that led to the restraining order.

Meanwhile, some stood and applauded class speaker Ryan Brown when he bowed his head for a moment of silence before his speech.

About 200 people attended a prayer vigil before the ceremony, and a placard-carrying atheist and a Pentecostal minister got into a shouting match.

In spite of the turbulent atmosphere, Appenheimer said she wasn't upset by the way things turned out.

"It's my graduation. I'm happy," she said. "I think [the lawsuit] was worth it. We changed things, we righted a wrong and made something better than it was before. I learned that when you believe in something, you should stand up for it."

Graduate Annie White disagreed, saying many class members wanted to demonstrate that "God was a part of our graduation."

Superintendent Lee Edwards said the school district might appeal the court's ruling. He said the invocation and benediction prayers usually said at the ceremony were innocuous, and "You would have to have been working pretty hard to be offended."

School district officials defended the prayer on grounds that students, not administrators, were in charge of graduation.

The Supreme Court's landmark 1962 decision outlawed organized prayer in public schools. In 1992, the justices barred clergy-led prayers at graduations, and last year, the court barred officials from letting students lead crowds in prayer before football games.