No. Not even a shot needs to be fired in order for it to be effective.
This never made the mainstream news because Newtown happened just a few days later.
http://www.easybakegunclub.com/blog/...he-Full-S.html
My brother is a teacher. He has signed up to get his CCW permit in our state. His wife is also a teacher, and he'd like for her to do the same. If it ever becomes legal for a teacher to carry at school in our state, my brother will do so. (He was Army ROTC and planned on being an Army lifer until a medical issue lost him his scholarship).