Here's an example of politics creeping into the classroom in the name of science.
There are various theories of the origin of the universe. Of course there is creationism, which is not scientific because it is not falsifiable. That doesn't mean that it isn't what actually happened, but it does mean that there is a case for not presenting it in science classes.
What is usually taught is the "big bang" theory. There are problems with this theory too - experiments must be repeatable. If we can't create new universes, we can't buy off the "big bang" theory as scientific, though thousands of scientists might prefer it to creationism.
So it would seem that the appropriate thing to do in primary and secondary schools' science classes would be to confine instruction to scientific theories alone, which basically means leaving the origin of the universe as an unanswered question. This also provides an excellent opportunity to demonstrate that science cannot explain everything, even in principle. IMO science cannot be properly understood without noting its limitations, and failing to note them introduces the risk of turning science into a religion itself.
Unfortunately, this opportunity is usually squandered. Instead the big bang theory is taught, and efforts to give equal time to another non-scientific theory, creationism, are treated as the work of cranks.
This is not science, it is politics. I'll leave the issue of whether religion ought to be taught in public schools to the Supreme Court. But it's fair to say that if neither creationism nor alternative theories of the origin of the universe are scientific, then neither should be taught in science class. Under such circumstances teaching the big bang as if it negates religious claims is an unjustifiable affront to religious people.