At it's most fundamental level, the notion of "science" seeks facts, provable and replicatable facts. In pursuit of this, there's an entire system of how such knowledge is pursued, vetted, and assigned a degree of certainty.
At it's most fundamental level, religion seeks converts. In pursuit of them, there's an entire system of how such converts are to be converted, via fear, relief from suffering, and of course indoctrinated belief in blatantly non-factual mythology and doctrine.
The former has every reason to be presented in public-school classrooms.
