Intelligent Design is NOT a scientific theory, as has already been determined by both the US federal court system and by professional scientific organizations.
In 2005, the Kitzmiller v. Dover Area School District case was the first direct challenge brought in the United States federal courts against a public school district that changed its biology teaching curriculum to require that intelligent design was to be presented as an alternative to evolutionary theory, with Of Pandas and People to be used as a reference book. The judge, John E. Jones III, who was a conservative church-going Republican appointed by G. W. Bush in 2002, ruled, in light of the evidence presented, that intelligent design is not a scientific theory as currently defined by the National Academy of Science, but is a form of creationism, and that the school board policy violated the Establishment Clause of the First Amendment to the United States Constitution prohibiting the establishment of religion. Anyone unfamiliar with this may take a look at some of these resources:
“Kitzmiller v. Dover: Intelligent Design on Trial,” National Center for Science Education, October 17, 2008, http://ncse.com/creationism/legal/intelligent-design-trial-kitzmiller-v-dover.
“Intelligent Design on Trial,” a 2-hour NOVA television special, aired Nov 13, 2007, available for free viewing on-line at http://www.pbs.org/wgbh/nova/evolution/intelligent-design-trial.html.
The wikipedia article: http://en.wikipedia.org/wiki/Kitzmiller_v._Dover_Area_School_District.
“Intelligent Design,” National Academy of Sciences page, http://nationalacademies.org/evolution/IntelligentDesign.html.
“Science and Creationism: A View from the National Academy of Sciences,” 2nd Edition, 1999, http://www.nap.edu/openbook.php?record_id=6024.
An on-line dialogue about Intelligent Design from 2008: https://docs.google.com/document/d/1ylKVTHUU_MOs3ImdROKd1nR0v-NCYR6n9i-pxIwv6FI/edit?hl=en_US&authkey=CMz9pN8B .
The American Association for the advancement of Science, AAAS Board Resolution on Intelligent Design Theory, 2002, http://www.aaas.org/news/releases/2002/1106id2.shtml.
Some additional sources on evolution are available here:
A list of resources on evolution at one of my own sites, on a page written in response to questions from a former high school class mate of mine and fellow church youth-group member: https://sites.google.com/site/investigatingchristianity/home/thebigquestions/5-evolution
A compilation of sources on evolution that I made for Darwin Day in 2008: https://docs.google.com/document/d/16xzeLBXDFh1moDyxR0wRrazOg9_eBzDPXR0nlfKHzuc/edit?hl=en_US.
A general scientific and historical time-line (https://sites.google.com/site/investigatingchristianity/home/scientific-and-historical-time-line ) compared to the unhistorical Biblical time-line (https://sites.google.com/site/investigatingchristianity/home/otchrono ).
Intelligent Design is but the latest version of creationism. The traditional Jewish and Christian notions of creationism come from the Bible, specifically Genesis, which was written in a relatively primitive and superstitious age and is not a scientific, historical, or reliable source of information on history or human development. See https://sites.google.com/site/investigatingchristianity/home/otchrono.