Bro my parents are the same way but i just kept on doing it secretly, getting caught every now and then and i talk about it in front of them all the time. I've found that I slowly molded them into a more soothed state about the whole idea. When I got caught the punishments were rough and they think ive stopped but i still tell them that i do it every now and again just to keep them on their toes. I'm almost 18 so I still have the rest of this school year before freedom just be a ninja when you smoke. thats my advice