Yes and no: the Establishment Clause of the First Amendment prevents the government from overtly favoring one religion over another, so if they want Bible studies in public schools, they’ll have to equitably provide Catholics, Satanists, Muslims, Witches, Polytheists, etc. the same deference and inclusion in teaching materials as Protestant Christianity.
There’s nothing in the constitution that prevents Bible Studies from being mandatory, it’s existed in the past.
Yes and no: the Establishment Clause of the First Amendment prevents the government from overtly favoring one religion over another, so if they want Bible studies in public schools, they’ll have to equitably provide Catholics, Satanists, Muslims, Witches, Polytheists, etc. the same deference and inclusion in teaching materials as Protestant Christianity.