The problem is not that religion is addressed in public schools, it is how it is addressed. Creationism, no matter how much you believe it is true, does not
ever belong in a science classroom.
Also, the vast majority of america needs to be educated as to what "theory" means in science. A scientific theory (like Newton's theory of gravitation) is a robust, hearty beast. It has withstood the constant tests and scrutiny given to it, and is supported by evidence, other theory, and other disciplines.
Also, just because nobody witnessed the beginning of the universe does not mean that we cannot discern how it started. If someone throws a rock into a pond, and you come up a minute later, all you see is ripples, concentric circles spreaing out from the point of impact. Without knowing anything else, you can tell where the impact was. By measuring the properties of the waves (ampliude, length, speed, etc.) you could tell when the object hit, and how big it was. You could even tell how fast and at what angle it hit the water. The police do not need to see the gun or watch the killing to be able to solve a murder case.
About conservation of matter:
The law of conservation of matter is an extension of the law of conservation of energy. New measurements made by astrophysicists seem to confirm that matter energy+ other energy = 0. The universe is quite literally nothing. This also bolsters the Big Bang theory. In quantum mechanics, you can actually get an infinite amount of energy from nothing. The catch is, the amount of time you can borrow the energy is inversely proportional to the amount you borrow. (See Uncertainty Priciple, Heisenberg's). So, on a tiny scale, the universe is boiling, wth particles appearing and disappearing with a lifetime determined by old Heisenberg. Any of these fluctuations could, in theory, "neck" off and grow into a universe. (See Multiverse, The). Since our universe comes out to a net sum of zero, it could, (mathematically), last an infinite amount of time.
It is true that many creation scientists disagree with dating methods used. They are, indeed, in the vast minority. The top theories about how dating methods could be wrong usually include something about a variable spped of light. If the spped of light were even the tiniest bit variable, we would be able to detect it. For instance, the microwave spectrum of O=C=S, used in physical chemistry, is known to
seventeen decimal places. Even the tiniest fluctuation in c would be detectable.
Plus, if the bible is literal, we are all horrifically inbred. Twice over. Besides having no evidence, genetically or otherwise, that's justy plain creepy.