since they're all pissed and say you have to move out if you don't stop, my advice is to stop. but if you feel like you really want to keep smoking, then smoke only every once in awhile. maybe once a week, or once every two weeks, if that much even. i wouldn't advise trying pass a drug test with someone else's piss, because if they found out you'd be in a hell of a lot of trouble i'm sure.

i was caught by my parents two years ago, and it was bad, but i was 18 then, and i moved out of the house and off to school a month after i got caught anyways. i still smoke, and my parents have no clue.

if you really want to try to pass a drug test with a substitution method, i recommend checking out the threads on drug testing. risky though, if they're gonna make you move out if you don't stop. might be best to stop for a bit, and pick it back up once things have calmed down.