Science has had a monopoly on American science education every since... and rightly so.
It is a lot like Religion having a monopoly in religion classes or writing having a monopoly in writing class.
Further, Darwin is ancient history. There are many components to science that goes beyond darwin's incomplete and partially incorrect theories.
Yes, Darwin was a long, long time ago, and much of what he wrote is now dismissed--notably his racist comments. But "Darwinism" is the name everyone uses, including the courts, to refer to evolutionary theory. Or, if you prefer, Neo-Darwinism.
You don't really deal with the monopoly issue, or the issue of activist judges telling communities what they can and cannot teach in their schools.
I have read a number of books and articles on intelligent design, and it makes a lot of scientific sense. Simply to rule it out as "religious" is bigoted and narrow-minded. Monopolistic, in fact.
As for science in science classes and religion in religion classes, religion isn't allowed in the schools, at least not in any reasonable way. Some require students to learn about Islam, but any religion or morality that might be of use in making them better citizens and better human beings is ruled out.
No, the shrill insistence on no competition and the ad hominem attacks on all these threads suggest that Darwinists have a feeling that their backs are to the wall and that their beliefs are incapable of standing up to any kind of rigorous questioning. But maybe they can perpetuate their monopoly if activist judges give them the exclusive right to brainwash our children.