New York parents said their children came home teary-eyed on Monday, Dec. 2, after a teacher told her first graders that Santa Claus and the Tooth Fairy aren’t real.

The incident happened at Public School 321 in Brooklyn as a teacher did some age-inappropriate myth-busting during a lesson about “convincing,” News12 reported.

One first-grader came home asking, “’but that’s not right, right?’” his concerned mother said.

Even though the school told the parents that the teacher was a substitute, they are still upset that the man “destroyed” their children’s belief, especially that the holiday season is approaching.

“Stuff like this, that their parents lie to them, I think is damaging to kids,” the mother said. “It’s three weeks before Christmas. These kids are six years old.”

 In a letter sent out to parents, the principal said she was extremely upset to hear about what happened and the staff member was being investigated. In the meantime, the teacher has been removed from the classroom.

“I guarantee you that this substitute will not be in class 1-216 again,” the letter read. “We take this very seriously.”

Meanwhile, the parents said that just want their children to understand that everyone is entitled to their own thoughts.