It is ridiculous.
I just recently read a story where an elementary school student was suspended because he formed his fingers into the shape of a gun (vertical thumb, horizontal index finger, other 3 fingers curled into his palm), pointed his index finger at another student, and said "BANG!" The other student didn't notice, nor did any of his other classmates ... but the teacher noticed. He was sent to the principal's office, his parents were called, and he was suspended for three days.
Were the administrators so stupid as to think his hand was an
actual gun? He's a 10-year-old boy, not Robocop. (And even Robocop had a separate firearm - it wasn't built into his hand.)
Guns are no joking matter, but what led the administrators to think the kid needed to miss three days of education for pointing a finger and saying "BANG"? They could have just sat down with him and his parents and explained that the gesture was inappropriate.