The problem here is school districts are locally controlled. And it sounds like this a deeply religious community given that there seems to be a number of students and parents who support this and the ones who don't either seem to be afraid to speak out or are otherwise tempering their opinions. Complain to the school board? Well they're all gonna be religious nutjobs. Complain to the state? Yeah this is Louisiana, I doubt the state bureaucrats are much less religious. And any local judges, they're very likely old, white, reactionary assholes who think "maybe this isn't legal but it's good for these kids to get some gospel learnin' so I'll allow it". And we all know there's no way the federal government will do anything about it. This is just what very slow motion balkanization looks like.