I'm a sophomore he's a senior

Hi I'm turning 16 in 2 months as well as starting my sophomore year of high school and there is this guy that I have had a crush on for almost a full year. Even through the whole summer that I haven't seen him at school. I haven't said anything to him all year because he had a girlfriend and I wouldn't go that far (I mean I'm naive but not THAT naive). Now that I'm not sure if he is seeing anyone I want to ask him out and see what happens. I just want advice in general here. Opinions (nicely put opinions at that) would be great too. Is it a bad idea? Should I go for it? Or should I just become friends with him? We haven't talked that much as I was pretty much fresh meat last year and the most contact we have had is one of my close junior friends asking him if I can use his phone. Also if you have any advice on asking him out that would be great. I can have some super bad social anxiety sometimes and I've only ever asked out one boy before. Overall any advice/opinions would be GREAT.

Sorry if this was a messy post I've never really talked about this before with someone. I usually just drool over him to my friends.