Why don't we teach humour in school?

Why don't we teach humour in schools? In some ways I think humour is one of the most important commodities around. If you make the receptionist laugh you’re much more likely to talk to his or her boss.  The best advertising campaigns i can think of all were really funny. Humour stays with you . You remember funny things for a long time. I know I’m constantly trying to preserve my funniest memories because i don't want to loose them. Don't you just hate it when you come up against some one who just has no sense of humour?  I don't remember a single lesson in school, even drama that talked about the awesome power of humour.