I just don't see any scientific way to prove the existence of God. Can we use the Hubble telescope to see him? Can we check for the DNA of the Holy Spirit?
You can make the argument that God started the whole thing, but that's a theological premise, not a scientific one. Why would we want to introduce that debate into schools, for example?
But we can turn that around, too. You can also make the argument that the whole thing just sort of randomly happened, in some way. But that, too, is a "theological" premise, and not a scientific one. Why would we want to introduce that debate into schools?
I think the only "scientific" way to prove the existence of God would be if He came down to Earth in a real and tangible way, so that nobody could deny His existence. Like, maybe by showing up as a human being, or something. And maybe being killed and rising from the dead....
Or (and here we're getting into theology) maybe for whatever reason he just makes Himself known to us individually.