But in some corners of the country, especially in the rural South, open prayer and Christian symbols have never really disappeared from schools, with what legal advocates call brazen violations of the law coming to light many times each year.

At a school assembly here in South Carolina on Sept. 1, a preacher described how Christ saved him from drugs, telling his rapt audience that “a relationship with Jesus is what you need more than anything else.” A rapper shouted the Lord’s praise to a light show and most of the audience stepped forward to pledge themselves to Christ while a few remained, uncomfortable, in their seats.