Once again, state legislatures have been turned into battlegrounds by lawmakers who seem intent on slipping religion into the science classroom. As in years past, most of these bills simply seek to protect teachers who introduce spurious criticisms of evolution into their lesson plans. But South Dakota has the distinction of attempting to specifically protect the teaching of intelligent design, something that has already been determined to be unconstitutional following a bruising court defeat.

As tracked by the National Center for Science Education, four states are considering a total of five bills; Missouri has the honor of having two bills going at once, while Virginia and Oklahoma have one. The Virginia bill is fairly typical of these. It would prevent local school boards and administrations from punishing teachers who help students "analyze, critique, and review" scientific theories in their classrooms. In the past, these bills have singled out evolution as a topic that's meant to be critiqued—one Missouri bill still does—but lately that's often been dropped in favor of generic language like "scientific controversies" (see, for example, the Oklahoma bill).

Based on the evolutionary history of these bills, it's clear that they were originally intended to encourage teachers who wished to introduce criticisms of evolution, many of which have been published by the creationist and intelligent design movements. However, in an attempt to avoid legal scrutiny, the bills' authors have been turning to increasingly generic language.

That said, this year's bills include two distinct variations on the theme. One is the second Missouri bill, which would require schools to develop "a mechanism where a parent can choose to remove the student from any part of the district's or school's instruction on evolution." And the second is the South Dakota bill, which would see any teacher that introduced intelligent design into their science classroom protected from disciplinary action, even though that instruction has been declared an unconstitutional imposition of religion.

"[This bill] is a recipe for disaster," said NCSE Executive Director Ann Reid. "If enacted, school districts are going to find themselves caught between a rock and a hard place—and they'll wind up in court."

If the long-running battle over evolution interests you, stay tuned to Ars. Next Tuesday, we'll have two reporters at the Creation Museum to watch its founder debate Bill Nye, the Science Guy.