What should I do with those annoying girls who has a crush on my boyfriend?

Should I talk to them?Tell them that it's inappropriate?They pester him even if i'm there. They don't get it that their crush already has a girlfriend. I am talking about girls who shriek when they see him,highschool girls for Christ's sake. They're like his stalkers!They know everything out him. My boyfriend says that I should ignore them coz he ignores them too. But i don't know,it gets pretty irritating especially if we go to the mall. Uhh,freaks.