According to First Liberty Institute, a legal religious freedom organisation, Calvary Chapel Dayton Valley has taken part in the Lyon County School District community flyer distribution program for years.
The program allows community organisation to share flyers about various activities including outdoor programs, sports leagues, and Halloween parties.
However, the school district changed its policy in June after a parent complained about the church's religious speech on the flyers.
It refused to distribute flyers about Calvary Chapel's Outdoor Excursions program, Harvest Festival, and Youth Nights (which include basketball and air hockey) because they included phrases such as "worship music", "good news" and "devotional".
It also asked for cross images and a Proverbs quote to me removed from one of its flyers.
Stephanie Taub, Counsel for First Liberty, which is defending the church, said the district should end "its discriminatory new policy".
She added: "The First Amendment requires school districts to be neutral toward religion.
"They may not single out a church's flyers for censorship, and they may not force a church to scrub the flyers of any religious language. That is hostility toward religion."
Amber Williams, Associate Attorney with Lipson Neilson, which is also supporting the church said: "Not only is this practice unconstitutional, it defeats the very purpose of providing community information.
"By removing all religious references from the flyers, parents and students have no way of knowing about the nature of the events and cannot make informed decisions about whether to attend."
Both legal teams sent a joint letter to the school district on Wednesday demanding it reverse its policy.