April 29, 2009 -- Students and parents at two Wisconsin public high schools are suing the school district to prevent this June's graduation ceremonies from being held inside a local mega church.

A lawsuit filed last week by Americans United for Separation of Church and State on behalf of nine students and parents in the Elmbrook, Wisc., school district, claims that conducting graduation ceremonies in a place of worship violates the Constitution and makes some attendees feel uncomfortable.

"Students literally have to walk up under a giant cross to get their diplomas," said Americans United's Executive Director Barry Lynn. The graduation ceremonies for Brookfield Central High School and Brookfield East High School, the two schools named in the suit, are set to take place at the 3,200-seat Elmbook Church on June 6 and 7.

"It's not an appropriate venue for a multi-cultural and multi-religious community," said Lynn.

None of the nine plaintiffs have been identified publically to prevent "social ostracism," according to the suit. A lawyer for Americans United declined to make them available to ABCNews.com for an interview.

The suit, filed in federal court in Milwaukee, is seeking a court order that would force the two schools to find an alternative venue for the graduation ceremonies.

One plaintiff, identified in the complaint as a senior set to graduate in Elmbrook Church this spring, said in court papers that seeing his older sibling graduate in the church made him feel "uncomfortable and upset."

"Photographs from that graduation include the cross, and serve as a permanent reminder of the discomfort that the ceremony's location caused," the students claim in the complaint.

Another plaintiff in the suit reported feeling "unwelcome" and "like an outsider" during a past graduation ceremony at the church because of the presence of Bibles and hymnals in the pews.

The complaint also notes the "immense" size of the cross that hangs in the church and the fact that it "appears directly in attendees' line of sight."

Heather Weaver, an attorney for the American Civil Liberties Union's religion program, which is not involved in this case, told ABCNews.com that graduations should not be held in churches when there are other workable options.

"When there are suitable alternative venues as appears to be the case here, public school students should not have to go to church to take part in the final event of their high school careers," said Weaver.

"The school district has the responsibility that all students of all faiths or no faith can attend without feeling religiously pressured," said Weaver.

Matt Gibson, the Elmbrook School District superintendent, told ABCNews.com that Elmbrook Church was originally chosen by students themselves after they requested the ceremonies be moved out of the schools – which had a limited amount of space for guests – and into an alternative venue with air-conditioning and handicapped accessibility.

"The students asked their principals if they could check out some other locations for their graduations and the principal said yes," said Gibson. "They looked at a variety of locations, and the one they settled on was the church's auditorium."

This scouting process has occurred every year since 2000 at Central High School and since 2002 at East High School. The church has been chosen each year as the venue for the graduation.

The first year the graduation was held at the non-denominational Christian church, Gibson said that the 15- to 20-foot tall cross that is noted in several of the plaintiff's complaints was obscured.

"The first year we held graduation at Elmbrook they veiled the cross," said Gibson. "Then the church decided that they wouldn't do that anymore and they would only remove temporary things – such as banners that are religious in nature but that can be put back up after graduation."

Mel Lawrenz, the senior pastor at Elmbrook Church, argues that the cross was never purposely veiled but was rather hidden by graduation decorations that were relocated in the following years so that the cross would be in full view.

Asked whether the church would be willing to veil the cross during this year's graduation ceremony, Lawrenz said that covering the cross would be "an insult to the identity of the church."

"Elmbrook Church has always tried to be a good neighbor and a resource to the community," said Lawrenz. "A wide variety of schools and other organizations have asked to use the Elmbrook facility for graduations, music events, and other community functions, and over the years we have heard widespread gratitude by these many groups for what they were able to accomplish in the facility."

"To cover the cross becomes more of a negative statement than accomplishing anything really practical," said Lawrenz. "Everybody knows a church building is being used."

Sarah Mucek, a 2001 graduate of Brookfield Central, said that she remembers the cross being "pretty visible" during her graduation.

"From my perspective, the facility was a church but the ceremony was completely secular and focused on the high school," said Mucek. "It did not mention any denomination or the church itself, so for me there was no problem."

Mucek said that while she does see where some people could take issue with the ceremony occurring in a church, she said that the way the facilities were used by the school were "nothing but welcoming and inclusive."

The church is also the nicest place in the area to host the event, according to Mucek.

"The church is absolutely the biggest venue in the area," she said. "If we did it at the school it would have had to be in the cafeteria and the facilities at Elmbrook are so much nicer."

Gibson said that there have always been a "handful" of complaints regarding the religious setting for public schools' graduation, but said that the Elmbrook Church remains the most sensible choice.

"I view this as a practical matter," said Gibson. "Questions have been raised periodically through the years by a handful of people and I don't discount them, I take them seriously. But the majority of students are OK with the church and as long as it's constitutional."

Gibson said the cost of holding the ceremonies at the church, which about $2,000 per school according to court documents, is on par with what it would cost to pay janitors overtime and crews for setting up and breaking down seating if the schools were to host the graduations at their respective campuses.

Students have consistently chosen the church for their graduations because it has more space and amenities than any of the other local options, including an exhibition center with half the number of seats as Elmbrook.

The church's 3,200-person capacity lets each student invite an unlimited number of guests. Graduating classes at the schools range from 350 to 400 students.

Gibson says that both schools are constructing improved gymnasiums that will have similar amenities as the church and are to be completed well before the next year's graduations.

"We've stated to people that we'll be moving the graduations back on campus in 2010," said Gibson.

Jay Sekulow, the chief counsel of the American Center for Law and Justice, a conservative civil liberties law firm that is dedicated to protecting religious freedoms, said that this is the first lawsuit of this kind that he's seen, despite the fact that many public high schools nationwide have traditionally used church property for graduation ceremonies.

Sekulow said that he believes American United's lawsuit is "ridiculous" and that constitutionally, there is no problem holding the graduation in a church.

"If this was a worship service for a public school then clearly there would be a problem," said Sekulow. "But it's not, a school is just using it for convenience."

"To those who say they're uncomfortable they're in a free country," said Sekulow. "They're going to see and hear things that they don't like, that's the price of freedom."