The move follows a ruling against the Santa Fe Independent School District in Galveston, Texas, stopping it from allowing students to take part in student-led prayers at matches, because this violated the constitutionally-required separation of church and state.

The Supreme Court's decision is expected to help clarify the law governing religious activities at schools.

The last major Supreme Court ruling concerning school prayers, announced in 1992, banned clergy-led prayers at graduation ceremonies.

But in 1993, the court refused to review a federal appeals court ruling in a Texas case that allowed student-led prayers at graduation ceremonies.

That ruling, which also set the law in Louisiana and Mississippi, was in direct conflict with a decision by another federal appeal court to ban student-led graduation prayers in nine other states.

Challenges

In the Galveston case, the Santa Fe Independent School District had allowed students to deliver any "message" or "invocation" over the public address system at home football games.

But following challenges from students and school officials, a court ruled that students' prayers at graduation ceremonies should be "non-sectarian and non-proselytising", and banned student-led prayers from football games altogether.

In the latest development, the school district's lawyers appealed against this ruling.

They argued that the constitution's treatment of religion is "better honoured through the neutral accommodation of student viewpoints, whether they be sectarian, ecumenical or religion-free, rather than through government censorship of the content of student prayers."