In August, the Kansas Board of Education gave preliminary approval to science standards that allow intelligent design-style alternatives to be discussed alongside evolution.

President Bush has also weighed in, saying schools should present both concepts.

Richard Thompson, president and chief counsel of the Thomas More Law Center, which is defending the school district, says Dover's policy takes a modest approach.

It requires teachers to read a statement that says intelligent design differs from Darwin's view and refers students to an intelligent-design textbook, "Of Pandas and People," for more information.

"All the Dover school board did was allow students to get a glimpse of a controversy that is really boiling over in the scientific community," Thompson said.

The Discovery Institute, a Seattle-based think tank that represents scholars who support intelligent design, opposes mandating it in public schools. Nevertheless, it considers the Dover lawsuit an attempt to squelch voluntary debates over evolution.

"It's Scopes in reverse. They're going to get a gag order to be placed on teachers across the country," said institute senior fellow John West.

To build their cases, each side is enlisting a battery of academic experts. Witnesses for the defense include biochemist Michael Behe of Lehigh University, who defended intelligent design in his 1996 book, "Darwin's Black Box: The Biochemical Challenge to Evolution."

Eugenie Scott, executive director of the National Center for Science Education, which supports teaching evolution in public schools, said the controversy has little to do with science, because mainstream scientists have rejected intelligent-design theory.

Intelligent design supporters "seem to have shifted virtually entirely to political and rhetorical efforts to sway the general public," Scott said. "The bitter truth is that there is no argument going on in the scientific community about whether evolution took place."