Do the words "zero tolerance" and "policy" ring any bells? I'd wager the teacher HAD to report it up the chain of command or risk being fired.
Does the word common sense ring any bells. A few pieces of metal is not a gun. I am 36 and when I was in school this would have been no big deal. Zero tolerance and policy? I would love to see the policy the policy that says you cannot bring scrap metal to school.