"Safety is their first concern and ours," she said. "We have taken the necessary steps."
However, school officials were not able to assuage the fears of some parents. Millward estimated that 20 to 25 parents pulled their children out of school. He said people are on edge because of the killings Tuesday at a high school in Littleton, Colo.
"I don't blame them. I'm a parent, too," he said.
Keedysville resident Linda Lebling said she got a call from her seventh-grade daughter at about 9:45 a.m. and drove to the school to get her.
"There were a ton of parents in the lobby trying to do the same thing," she said.
Despite assurances from school officials, Lebling said she still had concerns.
"At the time I left the school, I didn't feel that way," she said.
Rohrersville resident Lisa Horn said her daughter probably was more affected than other children by the shootings because the family moved to Washington County from Colorado last fall.
Horn said her daughter called her during first period after she heard a student had brought a gun to school.
"I don't know what the answer is. But I think the staff needs to buckle down and go class by class and find out what kids' fears are," she said.
Horn and Lebling both said they plan to meet with school officials on Monday morning before they allow their daughters to return to school.
"What do you do?" Horn said. "I can't just yank her out and home-school her."
School officials said the rumor began Thursday night, spreading by telephone and through a World Wide Web chat room.
Millward said he, school counselors and Boonsboro Middle's principal fielded calls on Thursday night from anxious parents. He said officials talked with one another and tried to assure parents their children would be safe.
"We thought we had it pretty much under control," he said. "It's a rumor that ran wild. The Internet is even more powerful than I thought."
Millward said the school called in the system's crisis response team and talked to students rumored to have weapons.
In addition, the Washington County Sheriff's Department sent four deputies to school before noon. They determined school officials were aware of the problem and had it under control, said Sgt. Tim Baker.
Baker called the rumors "totally unfounded."
Millward said he spent the day at Boonsboro Middle, walking the hallways and sitting in classes to reassure students that they were safe.
About 40 of the school's approximately 750 students were absent on Friday, Messina said. She said that is not an unusual absentee rate for a Friday.
But Millward said the students who were in school were distracted the entire day.
"It was not a good day here at Boonsboro Middle in terms of getting instruction done," he said.
Millward said the community has been on edge both because of the Colorado killings and because of rumors that a student who committed suicide last year had an assassination list of students and teachers at the school.
Maryland State Police and school officials investigated those rumors and dismissed them.
Jenny Belliotti, president of the Washington County Council of PTAs, said she received calls from upset parents on Friday. She said the school system needs to confront the rumors head on, perhaps with a town meeting.
"The rumor mill can do a lot more damage than the truth can," she said.