I can somewhat understand that but some of the positions being proffered by those on the right seem to violate the principle of separation of church & state.
The words "separation of church and state" do not appear in the U.S. Constitution, but that concept is enshrined in the very first freedom guaranteed by the First Amendment:
"Congress shall make no law respecting an establishment of religion." Known as the establishment clause, the opening lines of the First Amendment prohibit the government from creating an official religion or favoring one religion (or nonreligion) over another.
What is currently happening in some states, and being advanced by republicans, is the display of the Ten Commandments and prayer in public schools. In Louisiana the governor has stated that all public schools and universities must display the Ten Commandments by January. His answer to parents that are uncomfortable with this? "Tell your child not to look."
I'm Jewish and if I has a child that had a child attending public school in Louisiana, or a public school in a state that mandates prayer, I would not be happy. Muslims would be right to feel the same way.
If you feel that positions that the left holds about situations similar to what is going on in some schools is "anti-religious," I would argue that your opinion is misguided. If parents want their children to attend schools where religion is part of the education, they should have their children attend schools offering that, not a public school.