you gotta remember teaching the controversy of evolution has won 8 states already, thats over 16 percent of the nation in a little over a decade. I assume in the next 50-75 years the rest of the nation will be teaching the controversy.
That is largely because the "controversy" they purport to teach isn't really a "controversy".
There's always questions in science, but the level of "controversy" in evolution is so very small. The whole desire to "teach the controversy" is limited to only those things which impinge on a RELIGION's views.
How many "controversies" are taught in quantum mechanics? Well certainly there are questions in that field, but you don't see people marching to have disclaimers put in science books.
Evolution is a pretty solid hypothesis. NOt perfect, but CERTAINLY nowhere nearly as controversial as specific religious organizations would like.
Science is taught in the earliest levels using the best available evidence and the least controversial stuff.
Only when the students are able to understand the scale of the questions are the questions delved into.
so back to the evidence, have you yet read "signature of the cell" by stephen meyer?
it basically asks how things like the double helix can evolve?
I have not read Meyer's book but I am familiar with him.
The problems with this sort of thing come down to a couple points:
1. When one is looking at a system that has the ability to "adapt" to and has had sufficient time in a given niche then it would be nearly impossible to differentiate between successful adaptation and some "original design".
2. When the ONLY way to find evidence for the designer is in "information entropy" it becomes even more questionable. Think about the nature of a "designer" capable of designing all of life on the earth. This being should of course be far more obvious and unable to hide so effectively. If the only way to know it is there is to rely on a rather hyper-complex concept such as information entropy (when most people don't even understand basic entropy in thermo let alone this sort of thing) it makes me question why I should prefer an "intelligent designer" to an adapted organism/structure.
Now your question about DNA, well that's actually quite good! And interestingly enough DNA is simply a chemical. Just like any number of chemicals in the world around you that follows very strict, relatively simple physical rules.
When you put water in the refrigerator you get ice. Ice is a highly organized structure of the molecules of water. In fact we see crystals spontaneously form in nature all the time without the need of a "designer' because the chemicals HAVE to conform in certain ways based on their CHARGE, SIZE, and BONDS.
DNA is very much like that. It essentially has to form a helix (which is NOT uncommon in many macromolecules) due to the nature of the bonds and the order in which the molecules are stacked.
DNA becomes "magical" in this discussion NOT because it is somehow magical but because it is a big molecule that people know is related to life. But it is little different to many regular polymers that you may experience in the world that don't carry for you (or other religious people) any sort of mystical meaning. (There are some vinyl polymers with a helical structure if I recall correctly, and then some starches take on a helical structure).
There is no reason to assume that these structures are somehow special apart from the basic "energy minimization" and "conformational" rules that govern regular chemicals.