Mystic Valley Regional Charter School in Malden has removed references to God, Sunday school, and worship services from a sign outside a former Baptist church it owns, after parents and a civil rights group claimed the public school appeared to be endorsing religion.
The American Civil Liberties Union of Massachusetts filed a complaint last month with the state Department of Elementary and Secondary Education on behalf of some Mystic Valley parents, who said listings for the Maplewood Baptist Church should not be displayed on school property.
"It was really bad judgment on their part," said Sarah Wunsch, deputy legal director for the ACLU in Boston. "It seemed to link the school to the church. You cannot express religious views on a [public] school sign."
Fran Brown, chairman of the school's board of trustees, said confusion over the church and charter school sign is a "misunderstanding . . . There is no connection between the church and school."
Mystic Valley, which has 1,489 students in kindergarten through grade 12 and is one of the state's largest charter schools, bought the former Maplewood Baptist Church on Salem Street in February 2014 for $800,000, according to property records.
The school also agreed to a five-year lease with Maplewood Baptist that allows the congregation to hold religious services in the former church on Sundays, Brown said.
The pews were removed from the sanctuary, which was converted into space for small group learning and meetings. Other areas of the church were turned into office space, Brown said.
For more than a year, however, Maplewood Baptist's sign stayed out front, unchanged.
This fall, after the building was repainted, the church's name was removed from the two-sided sign and replaced with the school's name and logo. But a listing for church services, religious education, and the congregation's website remained, along with the message "God accepts broken hearts — but needs all the pieces."
"We never changed our sign," said Gary McClenthen, the church pastor. "What was on there before we sold the building was left there."
Brown said the school never intended to offend anyone. Mystic Valley's eclectic mix of real estate also includes two former Catholic elementary schools in Malden, but religious symbols are not displayed at either building.
"There was just a miscommunication," he said. "We probably didn't inform the church that they couldn't display their [service times] under our name."
While not widespread, the use of school buildings for religious services is not uncommon. Nor is it illegal, Wunsch of the ACLU said.
"Public spaces can be used by religious groups, so long as it's on the same basis as other community groups," Wunsch said, adding that a "public school cannot appear to be favoring a religious group."
Seven Mile Road Church, an evangelical congregation, has been renting space at Malden High School since April, said Brown, who is a member of the church. The church services are advertised on a temporary sign set out on the sidewalk on Sundays, he said.
Small congregations or startup churches often seek to rent alternative spaces, McClenthen noted. "It's very expensive to maintain a church building," he said.
The listing for church services and inspirational messages apparently didn't catch the attention of all parents at Mystic Valley.
"I hadn't seen the signs," said Ann Carroll, president of the charter school's PTO. "I hadn't heard about them taking them down, either."
But some parents felt the sign blurred the lines between the constitutional separation of church and state. They first complained to the school, then contacted the ACLU, Wunsch said.
Wunsch said she sent a letter on Dec. 15 to Martin Trice, executive director of Mystic Valley. One week later, after she did not receive a response from Mystic Valley, she filed a complaint with the state.
"Parents have complained to school administrators to no avail," said the complaint, which did not identify the parents.
Wunsch withdrew the complaint when the religious references were removed.
"It was amazing," she said. "Within one day of my filing the complaint, the offending messages were gone."
State education officials did not respond to requests for comment.
Kathy McCabe can be reached at Katherine.McCabe@globe.com.