I was in the snitchers shoes at roughly the same age: a seventh grader flashed a knife at me on the bus. I told. They didn't protect my identity. Later I was playing near my house and the boy with the knife came around the corner with an even older boy. They conferred. The older boy pulled a knife. I didn't stick around to find out what was next. The whole neighborhood heard me shrieking, and I don't care. This was a nice little suburb, not Chicago, though the boys were considerably older than 1st graders. Although I didn't report the other boy, since I didn't know the one and it wasn't at school, I never did see them again.
I would have objected if I were the father.