How would you discipline your 13 year old boy for.....?

You need to take a page from my parent's book. They went way overboard, but oh boy was it effective. I got a D on one of my report cards once, and they made me wear dresses to school every day until the next report card came back and my grades were up. And i'm not talking nice dresses, I mean the type of thing my mother would wear. It was embarrassing. You make him suffer like that and he'll straighten up real quick.