If we do that, then things like eugenics become morally acceptable in the science class
As far as the legitimate scientific community is concerned Eugenics has long been discredited. It's only been kept alive in the paranoid imaginings of fundie anti-science types. Sorry that reality has to intrude on your carefully crafted christianity uber alles/persecution complex.
And then when those students get out into the real world and start getting elected to public offices and making executive decisions, they will be making those decisions based on what they learned in science class.
Maybe in Political Science class. It's highly dountful that they would look at a political situatiton and think "What would Darwin do?". It's a bullshit arguement that no basis in reality.
The only reason I can think that someone would want to eliminate Christianity and the moral restraints that it brings
For starter no one mentioned "eliminating" christianity, they just suggested that it has no place in a science class, which is a perfectly reasonable idea, one that even find support from many christians.
What moral restraints? Aren't you the same people who bitch about atheists being against the death penalty? What is morally restraining about theses statements...
Thou shalt not suffer a witch to live?
If your family or friends say "come and worship other gods" you must kill them, your hand must be the first upon them?
If a girl is raped but didn't cry out load enough, or if your son is a drunkard that you must take the to the edge of town and stone them to death?
That's christianity's idea of moral restraint. No one in the scientific community promotes Eugenics, a fact of which I an sure you are already aware of, and the issue around euthanasia is about and individual with a terminal illness choosing that they want a painless death rather than lingering for months in agony while their body and quality of life deteriorates, it has never been about doctors, family members, or the government making that descesion, in fact to my knowledge no one has ever suggested such a thing except self righteous christians trying to prop up a strawman they can attack.
In summary, you are Lying for Jesus(TM) on each and every point, and as I recall your commandment doesn't say "Thou shalt not lie, except in jesus' name." Doesn't make you look like a very good christian does it now?