I agree with the above post, and also would like to point out that a key difference between school newspapers and privately owned ones is that public tax dollars are used for its publication, and it is typically distributed to the student body free of charge. Within that context, students do not have absolute freedom of the press (regrettably, in my opinion) and the public, through their elected school board members, can exert an influence over what is allowable in terms of stories and content.
While barring any discussion of God or religion seems a bit extreme, and it does matter in what part of the paper it is printed (editorial? feature?), the school does, as per the Hazelwood decision, have the ultimate editorial authority over the content of the newspaper.
To some degree, they even have authority over what is written by students about the school and school personnel on private blogs, social networking sites and message boards, so the courts have typically given schools quite a bit of power at censoring student-published content.