Anybody know how to convince parents?

My parents arn't THAT strict, in my opinion anyways. They have always been rather supportive of me wanting a motorcycle, however that was when I was young (6-10). Now that I'm old enough to actually buy one, they have expressed that they do not want me to ride. Now I don't know how to convince them I'll be careful. I say I'll take a driving course about motorcycles, that I'll get my licenses and all that stuff, but they wont budge. Anyways, hope you all could give me some ideas, thanks. Also what bike should I get first? Never been on a motorcycle before.