If it is off the table then science is not a search for the truth. A search for the truth does not allow for any possible explanation to be removed from discussion. The problem is that natural science has no explanation for the existence of nature. But since you have ruled out the supernatural from scientific study, you have no scientific way of determining how the natural came into existence.
The fact is that the presence of the natural presupposes the supernatural.
Evolutionist theory rests entirely upon a presupposition that life is an Immaculate Conception. Think about that one for a minute...
The "origin of species" is rooted in the idea of a singularity: the mechanics of the DNA molecule. All species of Terran life has it. Like the singularity of the "Big Bang" theory, the two are categorically inseparable as immaculate conceptions. It only takes a mere application of logic.
The perplexing question of human origin from a common ancestor to apes is even more problematic. According to evolutionary theory, humans (Homo sapiens) did not descend from apes, but from some "missing link."
Although Dr. Louis Leaky spent decades searching and found Zinjanthropus and Homo habilis, Olduvai Gorge gave no answers. Logic also suggests in order to "descend," there has to be something you descend "from" and something you ascend "to."
Evolutionary theory rooted in the universal human dissatisfaction for mortality is a vain search for human origin(s), an attempt to rationalize a yearning for connection to something eternal.
Now, since nobody knows the answers, it is only scientific method to consider all points of view on the issue in education. To do otherwise would be like students dancing around totems, with professors as witch doctors proclaiming intellectual taboos and making sacrifices.
This is far worse than what the ersatz secularists accuse the creationists of doing!