Guy trouble?

well i like this guy hes a little older but my parents would be fine with us going out. he kinda a bad boy witch i really like. some times he smiles at me and looks a me a few seconds until i look at him then he turns. we have never really talked because im really shy and i never see him talkin to people. im pretty good friends with his sister and our parents are friends so thats good right? and also when im around we just keep walkin past each other and he always sits behind me. do any of you think he likes me or is it a waste of time what do you think i should do???