Ryuken My honest advice, casually get closer to one or some people at school, eventually work your way up to asking "hey man, what do you and the guys usually do when you guys hang out?" after he tells you, reply with this "I would not mind handing too man, just not into smoking or drinking or anything like that." Most likely no one will care and they will invite you to hang out. I used to never drink or smoke anything in high school and I used to go to hang out with all types of people into all types of things all the time. Never was a problem.