We had prayer in school when I was a child in a very rural part of the state. No one was “forced” to, one person in particular didn’t, but me knowing that once person didn’t is really the point, I think. I don’t remember a single other person from my second grade class, but I remember him.
It isn’t getting kids to pray, or promoting religion, it is a way to single out the people who aren’t like-minded. It’s about obedience to a culture and identifying the other. Same with going to church and being part of the “respectable” community. You can do what you want and get away with it as long as you conform to the overall appearances.
If you are willing to bow your head, even if you don’t believe it, you pass for normal.