One way the OP can gauge how welcoming a school would be to see if a school has a diversity requirement and what that requirement would be. For example, UCLA has a diversity requirement, but there are plenty of classes that are not part of the grievance studies/sociology school that meet the requirement.
Go to SMU in Dallas. Super white, super christian, and extremely wealthy
To be fair, it was the over-the-top “…where he won’t be persecuted or forcibly indoctrinated” phrase that put some people off.
All colleges have a requirement that means a student, to be considered college educated, must understand other perspectives than the general/majority one, but it may mean many things: having an idea about non Christian religions, about groups that have been discriminated against or still are either because they were/are a minority (in the US or the rest of the world), about other worldviews and perspectives. Most colleges have two requirements, one focusing on diverse perspectives in the US (which could involve women’s history, African Americans and the diaspora, sociology of family, immigrant literature…) and one focusing on non American perspectives (IE., foreign language /culture, globalization, Chinese literature, African history before colonization, French-American relations , comparative governments…)
Even great book programs such as you find at St John’s or St Olaf (and many others) will include the classical texts from many parts of the world.
Brown, Amherst, Evergreen State?
I do think the OP’s choice of words was unfortunate and has gotten this discussion off to a difficult start. That often happens with someone new to the forum. I have a freshman in college. Based on what I’ve picked up from her reports, I don’t see any issue with religious views or any intolerance of Christians. It’s the “conservative” characterization that I think merits discussion and some preparation for what to expect.
Remember that what is considered conservative in mainstream society is considered very right wing at most liberal leaning colleges and universities. My kid is a Democrat, fervent Hillary supporter, very supportive of LGBTQ rights, but still has found herself pegged as a “conservative” for expressing even mild doubts and questions about things like microaggressions and safe spaces. But the biggest problem I see is that “conservative” is conflated with “white supremacist.” Especially if those conservative views are espoused by a cis-gendered, heteronormative, white Judeo-Christian (even worse if the person is male). Not by everyone, no, but those who do feel that way are very vocal, and frequently are the same kids who are active in student government.
Having said all that, I don’t feel qualified to rank the schools you mentioned, but will put in a plug for Harvey Mudd. The consortium as a whole certainly skews very liberal, but the presence of CMC (with actual admitted Republicans on the faculty) contributes to a campus with lively debates where your son would not be the sole conservative voice.
LeTourneau University in Texas is a solid evangelical Christian school with their main focus on STEM majors. They offer computer science, engineering, aviation, etc. Their Engineering Program is ABET certified.
Anglican Christians are much closer, indeed very close, to Roman Catholics and Episcopalians.
Evangelical is a very different part of Christian religion.
Anyone amused by the fact that the best way to get replies on your discussion is to bring up something religious?
^Actually, plenty of threads receive plenty of discussion here. I don’t find your statement true at all.
“He’d like to attend a strong STEM school, mainly a strong math school, but we’d like to find a place where a conservative Christian male won’t be persecuted or forcibly indoctrinated.”
Is this being driven by the parents desires or the student. First I see the “he” then the “we”. If this is driven more by parental concerns, I’d respectfully suggest letting the son choose schools where he feels comfortable.
LOL, should I have specified “all colleges with requirements have a requirement that means…” 
=)) :-h
The US Air Force Academy fits the bill for a strong STEM school with a conservative evangelical Christian bent to its faculty and students, which is unfortunate for an institution of the US military.
Tech heavy schools, like RPI, WPI, and Case, are mostly apolitical. Based on the description of your son’s stats, they would be safeties for him.
The words “persecute” and “indoctrinate” are inflammatory and invite some of the comments on this thread.
@NoVADad99 Do you think that is true for all the military academies or is it more prominent at USAFA?
The USAFA has been noted for its strong evangelical Christian bent for about the last 20 years. There has been reports of a hostile environment to non-Christians or those who don’t have strong evangelical beliefs and want to have a true separation of church and state environment in a government run high education institution. This is particular to the USAFA and does not apply to any of the other academies. I think the USAFA’s location in Colorado Springs, which is home to at least one national evangelical organization, has something to do with this.
I’m a former USAF officer, and I knew of one USAFA graduate from the early 90s who was very evangelical Christian. I consider him to be a friend, but it’s one data point. That said, the USAF officer corp seems, at least to me, to be more of that flavor than the other services.
In a STEM environment, what would constitute persecution or indoctrination? Since it’s a scientific and math based curriculum for engineering and science, how would a religious Christian reconcile a biblical interpretation of the universe vs. modern astrophysics, and the scientific understanding of our universe? How about climate change, or evolution?
My kid is a Mudder. Mudd is actually quite pro-active in areas like safe spaces, reminding students well ahead of Halloween to be considerate of others in their choices of costumes, etc. Their office of diversity is active and there are several diversity-oriented student groups on campus. Transgender students are welcome, and the school website has a section on steps to take if transitioning while at Mudd (not uncommon for college students to do so). There are also several gender neutral bathrooms on campus. Mudd has also avoided some of the protests and strife between students and administration that hit some of the other 5Cs this past year, partly because they are quite pro-active on these issues.
That said, there is also a 3C Intervarsity Christian organization (not sure which 3 colleges, but Mudd is one of them), And my (non-Catholic) kid actually goes to Mass sometimes with her friends (junior, I knew she went a few times freshman year, but she mentioned that she went just a couple of weeks ago, too).
Now… if that is “indoctrination” in your mind, OP, then Mudd probably isn’t the school for your kid. Although so many times the parents are more concerned about this than their kids are…
I would go online and check out the student groups. See if there are large active Christian groups. As long as there is a critical mass your kid should find his peeps even if the school overall has a liberal reputation.
“spit out”?.. the aggressiveness of your reply seems to reinforce the OP’s concern, IMO.
I think it’s really disingenuous of many posters to pretend that a student who would express for example, a pro-life position in most college classrooms wouldn’t get some hard push back which if directed at a non-white, non-male student would qualify as at least a micro-aggression. The reason this caught my attention is that today a friend of mine told me that her daughter, who is a freshman at a well regarded university, has a professor who expressed the opinion (in class) that he has total contempt for anyone who isn’t pro-choice. This is a very bright girl who happens to be Roman Catholic and she correctly concluded that she would not be wise to express her own thoughts on this matter and that there would clearly be no room for an open and honest exchange of ideas there. She is just keeping her head down and protecting her grade.
So can we please stop pretending that this concern is completely unfounded simply because you may not agree with the OP’s beliefs?
It is interesting how when someone comes on this forum and asks for a good school for their LGT kids, there is plenty of concern and hand holding. When someone has religious concerns about their kids education, the response is 180 degrees different. So much for tolerance and diversity.