Albert Einstein once said, "The definition of insanity is doing the same thing over and over again and expecting different results".
Epperson v. Arkansas, 393 U.S. 97 (1968), was a United States Supreme Court case that invalidated an Arkansas statute that prohibited the teaching of human evolution in the public schools. The Court held that the First Amendment to the United States Constitution prohibits a state from requiring, in the words of the majority opinion, "that teaching and learning must be tailored to the principles or prohibitions of any religious sect or dogma." The Supreme Court declared the Arkansas statute unconstitutional because it violated the Establishment Clause of the First Amendment. http://en.wikipedia.org/wiki/Epperson_v._Arkansas
Daniel v. Waters was a 1975 legal case in which the United States Court of Appeals for the Sixth Circuit struck down Tennessee's law regarding the teaching of "equal time" of evolution and creationism in public school science classes because it violated the Establishment clause of the US Constitution. http://en.wikipedia.org/wiki/Daniel_v._Waters
Hendren et al. v. Campbell et al. was a 1977 ruling by an Indiana state superior court that the young-earth creationist textbook Biology: A Search For Order In Complexity, published by the Creation Research Society and promoted through the Institute for Creation Research, could not be used in Indiana public schools. The ruling declared: "The question is whether a text obviously designed to present only the view of Biblical Creationism in a favorable light is constitutionally acceptable in the public schools of Indiana. Two hundred years of constitutional government demand that the answer be no." http://en.wikipedia.org/wiki/Hendren_v._Campbell
McLean v. Arkansas Board of Education, 529 F. Supp. 1255, 1258-1264 (ED Ark. 1982), was a 1981 legal case in Arkansas which ruled that the Arkansas "Balanced Treatment for Creation-Science and Evolution-Science Act" (Act 590) was unconstitutional because it violated the establishment clause of the U.S. Constitution. The judge, William Overton, handed down his decision on January 5, 1982, giving a clear, specific definition of science as a basis for ruling that “creation science” is religion and is simply not science. http://en.wikipedia.org/wiki/McLean_v._Arkansas
Edwards v. Aguillard, 482 U.S. 578 (1987) was a case heard by the Supreme Court of the United States in 1987 regarding creationism. The Court ruled that a Louisiana law requiring that creation science be taught in public schools along with evolution was unconstitutional, because the law was specifically intended to advance a particular religion. http://en.wikipedia.org/wiki/Edwards_v._Aguillard
Tammy Kitzmiller, et al. v. Dover Area School District, et al. (400 F. Supp. 2d 707, Docket no. 4cv2688) was the first direct challenge brought in the United States federal courts against a public school district that required the presentation of intelligent design as an alternative to evolution as an "explanation of the origin of life."The plaintiffs successfully argued that intelligent design is a form of creationism, and that the school board policy thus violated the Establishment Clause of the First Amendment to the United States Constitution. http://en.wikipedia.org/wiki/Kitzmiller_v._Dover_Area_School_District