"Creation Science" often refers to old-school young-earth scientific creationism, the primary organizations for which are the Institute for Creation Research and the Creation Research Society. That their purposes are religious rather than scientific is evident in their own tenets/belief statements.
An excerpt from the ICR's tenets: (http://www.icr.org/tenets
All things in the universe were created and made by God in the six literal days of the Creation Week described in Genesis 1:1-2:3, and confirmed in Exodus 20:8-11. The creation record is factual, historical, and perspicuous; thus all theories of origins or development that involve evolution in any form are false. All things that now exist are sustained and ordered by God's providential care. However, a part of the spiritual creation, Satan and his angels, rebelled against God after the creation and are attempting to thwart His divine purposes in creation.
An excerpt from the CRS's Statement of Belief: (http://www.creationresearch.org/stmnt_of_belief.htm
The Bible is the written Word of God, and because it is inspired throughout, all its assertions are historically and scientifically true in the original autographs. To the student of nature this means that the account of origins in Genesis is a factual presentation of simple historical truths.
Leaving aside the obvious religious nature of these statements, requiring a commitment in advance to any
conclusion, rather than following where the evidence leads, is fundamentally incompatible with science. Thus, these are clearly not scientific organizations, despite their pretense.
Likely due to the failure of old-school Creation Science to sneak creationism into U.S. public school science classrooms, we now have a new, more "sciency", version of Creation Science called "Intelligent Design". This is primarily promoted by an organization called Discovery Institute, which, like the older ICR and CRS, also parades as a scientific research and education organization. Though the Discovery Institute has avoided overtly religious references in its literature, replacing "creator" with "intelligent designer", for example, and though it does not espouse the biblical literalism of old-school Creation Science, and accepts the fact of an old earth and even some limited evolution (so called "micro evolution"), its primarily religious nature is still apparent in its own statements about its mission and philosophy.
An excerpt from the Discovery Institute's "about" page: (http://www.discovery.org/about.php
Science and Culture. Scientific research and experimentation have produced staggering advances in our knowledge about the natural world, but they have also led to increasing abuse of science as the so-called “new atheists” have enlisted science to promote a materialistic worldview, to deny human freedom and dignity and to smother free inquiry. Our Center for Science and Culture works to defend free inquiry. It also seeks to counter the materialistic interpretation of science by demonstrating that life and the universe are the products of intelligent design and by challenging the materialistic conception of a self-existent, self-organizing universe and the Darwinian view that life developed through a blind and purposeless process.
Again we see an up-front commitment to a religious conclusion. DI's about page also reveals that this organization may be more about promoting religious right political ideology in general than promoting creationism specifically. What it is clearly NOT promoting, however, is science.