I can’t see how school officials would think this is acceptable:

A conservative civil liberties group has filed suit against a school in Greenbelt, Md., for violating the constitutional rights of a seventh-grader who was allegedly threatened with discipline for reading her Bible in school.
[…]
According to the student’s mother, Maryanne Mangum, Amber was reading her Bible after finishing her lunch when Rainey gave her a “verbal warning” to put the Bible away.
Amber was told she “was not allowed to read it, and if it happened again,” Amber would be punished, her mother said. “She didn’t take the Bible back to school.”
The school district’s policy, along with the guidelines under the U.S. Department of Education’s 2003 No Child Left Behind Act, gives students the right to read Bibles or other religious scriptures during lunch hour, recess or other non-instructional times.
“NCLBA, which is federal law that came in under the Bush administration, actually has this provision stating that students have a right to read their Bibles or other religious scriptures during the school day. It provides for that. It says also that you can actually get your federal funding taken away if you violate the NCLBA,” Whitehead explained.

I can’t stand that we have to add laws to protect a right that is recognized by the Constitution! Freedom to practice religion is our right and this situation is in clear violation of the that right.
And that would go for sharing our faith with others:

But Ellen Johnson, president of American Atheists, said most of the time, “right-wing groups” that file lawsuits “exaggerate what happened in school, and that is usually brought out later in the case.”
“What probably happened is this kid, I’ll bet you, was being disruptive. I bet this kid was proselytizing, was preaching, doing something that was annoying other kids and was told to stop. Kids don’t normally want to read the Bible at lunch time-I don’t care who they are. It’s just not something kids want to do,” said Johnson.

Even if she were proselytizing, it’s still her right to do so since our Constitution recognizes not only freedom to practice religion but also freedom of speech. We aren’t just free to broadcast profanity or sexually explicit material but freedom to proclaim or love of Christ and His offer of salvation.
Atheists and others don’t seem to understand that it’s part of our religion to share what we know about Christ with others and in America we have the freedom to practice our religion, all aspects of it.