I'm going to have to stop reading these evolution threads.
First off, bad as the general practice of pawning off evvolution may be, politically, scientists do not just pick an age for these things. The radiometric dating techiniques are not all that complex and can be used to sort of cross check one another. This, of course, says nothing about whether or not enough time actually exists for the calculations to be correct, but still, the ages set to rocks are not entirely arbitrary.
Having said that, the idea that Creation is not scientific is blatantly false. There are two things that make Creation hard for some people to believe. One is that they don't believe in God in the first place, and the other is, even if they do, they trust the scientific data more than the Biblical account or believe the Biblical account is symbolic of something and need not be read literally.
But how Creation comes to be scientific is really quite simple. All of science is based on building credibility through repeated observation and measurement and so forth. Why do people believe in God, then? (It is a prerequisiste to beleive in God before one can believe that God created the universe) They believe in Him because of their own experience of consciousness and free will, and because of historical evidence. The evidence of free will, while perhaps not definitive, is overwhelming. The documentation of spirituality and religion is also massive,. if not entirely conclusive. But, that is the basis. Ther physical basis is our own conscious lives, and the reliability of the Biblical version comes from ones feelings of trusing the people who bring the story to you.
This is exactly how evolution works. They have some physical evidence, but much of it is conjecture, it cannot be statistically analyzed to give "probabilities, the likelihood of it being true is a function of your worldview and what kinds of evidence and what kinds of people you trust most.
The creation of life, the universe and everything is such a deeply philosphical subject that it probably shouldn't be taught in science classes unless they are going to go ahead and give a fair understanding of the underlying philosophy and equal time to alternate concepts.
Every class I've ever taken where it comes up, creation gets discussed anyhow, so why not quit pretending they are not related and let's be open and talk aboit the thing.