For the last 30 years, supporters of school prayer and their civil libertarian opponents have been skirmishing over little bits of schoolyard pavement, each side claiming an inch of ground at a time.

So it came as a surprise last week when a federal appeals court decision seemed to hand over vast acreage of contested territory to the school prayer supporters in one afternoon. The decision applies only to Alabama schools, and its consequences are still being debated, but it seems to extend school prayer rights to a controversial new range of activities.

On Tuesday, the U.S. Court of Appeals for the 11th Circuit affirmed the right of students to pray over the school public address system and at public school ceremonies, such as graduations, sports events and assemblies, even when attendance at the events is mandatory.

The decision does set some limits. Most significantly, students--not teachers or administrators--must initiate the prayer, which has to be nonsectarian, and students cannot proselytize.

To supporters of school prayer, the decision is a wide territory conquered--"the most important school prayer case that has come up in years," writes the American Center for Law and Justice, the Christian group representing the defendants.

But to opponents, the decision establishes a dangerous precedent, forcing prayer on a captive audience of students who are required to attend public school functions.

"If it's a school-sponsored event, what's the difference if it's a teacher who stands up and says 'Let's all pray' or a student?" said Barry Lynn of Americans United for Separation of Church and State, who represented the plaintiff. "They're both coercive."

"And there is no such thing as 'nonsectarian, non-proselytizing,' " Lynn added. "When you say the phrase 'Dear God' you are already making a massive theological determination that there is one God."

The ruling adds a little clarity, at least in Alabama, to the broad gray area between two boundaries set by the Supreme Court. At one end, the court has allowed private prayer by a group of students; at the other, it has prohibited prayer officially sponsored by school officials.

So students in Bible clubs have the same rights to meet on school property as any other extracurricular group. But teachers may not lead students in prayer or promote religion in class.

But in between those two markers is a range of possible situations where prayers are initiated by students and recited at events that are mandatory for other students--a valedictorian blessing the senior class at graduation, a student reading a Bible passage at morning assembly or over the public address system, a linebacker saying a prayer in the huddle, a third-grader telling the story of David and Goliath during the reading hour.

Last week's decision ends a six-year fight between Christian conservatives led by former governor Fob James Jr. (R), who staked his last election on the fight and lost, and Michael Chandler, a retired vice principal of Valley Head High School in DeKalb County who was backed by the American Civil Liberties Union and Americans United for the Separation of Church and State.

In 1993, the Alabama Legislature passed a broad law permitting voluntary student-led prayer. The law was challenged, and U.S. District Judge Ira DeMent in Montgomery declared it unconstitutional and wrote an injunction against enforcing the law. Last week, the appeals court ruled that the injunction was too broad.

In his injunction, DeMent not only prohibited DeKalb school officials from organizing prayer but also from "permitting" prayer. The appeals court reversed that ruling, saying DeKalb schools could permit prayer and adding that they could do so in public settings, such as "aloud in a classroom, over the public address system, or as part of a program at school related assemblies and sporting events or at a graduation ceremony."

In language that pleased school prayer supporters, the three judges who wrote the decision declared that the Constitution "probably does not require a 'wall' " of separation between church and state, and argued that " 'Cleansing' our public schools of all religious expression . . . inevitably results in the 'establishment' of disbelief--atheism--as the State's religion."

Attorneys who litigate school prayer cases are watching Alabama to see how this ruling unfolds. Many are guessing at its impact on ongoing cases around the country--for example, one in California where two boys were told they had to remove every reference to "God" or "Jesus" from their graduation speeches and another in Medford, N.J., where a first-grade student was prohibited from reading parts of his Beginner's Bible in class.

Lynn and the ACLU lawyers will decide soon whether to appeal the ruling. Even their opponents said they hope they will do so, looking forward to an eventual resolution in the Supreme Court.