Sikhs have for generations used the option of having the kirpan they carry at all times be a pin or brooch in the appropriate shape. Somebody is BSing the state in this case.
That said, I really like the Sikh interpretation of the Indian idea of ahimsa or nonviolence. It’s basically that if you practice violence on the innocent, I will reintroduce a state of ahimsa by using my kirpan to bring an end to the violence.
Works for me.
In a world where drawing a police man with a gun is grounds to get you tossed from school they probably would not allow a pin either.