Who's in charge here?

Just heard last night that a teacher in Ventura had an unexploded 40mm round on his desk as a paperweight for years. He'd found it and thought it was an interesting paperweight. Well, two days ago, the thing blew up, and he lost part of his hand.

My question is--where was the principal when this schmo brought it into his classroom in the first place? What part of "no weapons in school" does he not understand?

Here's the story.