I had this as a primary example, but I am always wary of stories from sources that obviously have an axe to grind, so I checked into it a bit further.

I found an interview that seems to confirm the basics, although this is just a single source.

To balance this, I found this story from an opposing viewpoint.

I also found this take on it from Snopes, which is probably the most reasonable article I saw on the issue, and points out not only the perception of unfairness of the treatment of different religions, but also the radical agenda of some Christians on this subject.

The main point I am trying to make is not whether this kind of teaching is actually a bad thing from the standpoint of a reasonable person. It's that bringing Christianity into a school on this same level would have brought the wrath of two dozen liberal rights organizations down on the school.

There's this informal collection of news stories relating to displaying religion in schools as well. Unfortunately, most of the original links are dead, so take it for what it's worth. I have no guarantee that the transcriptions are accurate.

There's a good link on this page to Federal Guidelines on this issue. They seem quite reasonable, and it looks like some schools may be overstepping these boundaries.

The First Amendment says: "Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof."

It's in English, and seems quite clear to me. If a government-funded school teaches a particular religion as true, this is wrong. Someone wearing a crucifix to school, or a shirt with a picture of Jesus on it, is not, unless the school bought the T-shirts. Lately, it seems that even displaying one's religion so that it "offends" or "disturbs" any observer is enough to make a legal issue out of it. And it is obvious that some religions are more equal than others in this regard.

Needless to say, if our education system was not a government function, this wouldn't even be an issue.