Ciretta Mackenzie, a freshman at Epping High School, wore the gear to school on April 8 for its "America Day."
The event featured students wear clothing with red, white, and blue. Ciretta’s shirt also featured those colors.
But principal Brian Ernest called her into his office and told her she had to remove the shirt.
Telling him she had no replacement, he said she would have to be sequestered from the other students. She found a friend's sweatshirt to cover the shirt.
“I wasn’t upset. I was just kind of surprised, I guess,” she said. “I don’t think I should have been told to cover it up.”
The unusual decision prompted an investigation by Superintendent Valerie McKenney, who said that Ernest was in the wrong.
"The Epping School Board and Epping District’s position is that this event should not ever have taken place, and we are committed to the creation of a school environment that promotes open and free thought and dialogue," McKenney wrote in a letter to the school community.
“We have begun to draft a plan to move forward to promote civil discourse and diversity in our schools. In retrospect, I want to fully acknowledge my error in judgment and sincerely apologize if my actions were misinterpreted and offended anyone. That was never my intention," he said.
“I want our students to be free thinkers and be able to express their opinions in a respectful manner," he added.
Ciretta's mother said that the family accepted the apology.
“I allowed my personal political beliefs to overshadow that message, which ultimately is that I care deeply for the welfare and success of Sandy Creek students,” Emily Wemmer wrote in a letter to the school community and being moved to another job within the district.