And all the people shall say, Amen. Deuteronomy 27:17
There is ONLY one reason why certain politicians don't want your tuition assistance used at Christian schools----bigotry against religion......
Remember, in this case we are not talking about the govt. directly funding religious schools but rather- the tax paying parents receiving some tax money back (as taxpayers like anyone else) to be able to use it at the school of their choice. That includes a Christian school.
"The Supreme Court has dealt another blow to anti-Christian state 
laws.
On Tuesday, the high court ruled in Carson v. Makin that Maine's
law prohibiting government money from going to private religious
schools violates the First Amendment's Free Exercise of Religion clause.
Maine's tuition assistance program allowed qualified candidates to
receive government money to defray costs of tuition at schools of their
choice — with one caveat: Money could not go to "sectarian" schools.
The plaintiffs in this case had chosen Bangor Christian Schools and
Temple Academy as their private schools of choice, but the government
deemed them "sectarian," and they were disqualified from receiving
government funds.
Chief Justice John Roberts, writing for the majority (which
includes Justices Clarence Thomas, Samuel Alito, Neil Gorsuch, Brett
Kavanaugh and Amy Coney Barrett), noted, "The State pays tuition for
certain students at private schools — so long as the schools are not
religious. That is discrimination against religion." ChurchMilitant