I was in your position last year, boy came at the beginning of yr 11- I liked him from then all the way through to the end of yr 12. We were somewhat friendly with each other, internet buddies so to speak... I got to the last day of school where we took photos with each other and he wrote a message in my Year 12 book.
The crush continued on until three months ago when I finally let it slip to people that I liked him. All of a sudden, I knew he didnt feel the same way all along and we would never be more than friends. It wasn't devastating and it wasn't that big of a deal, I just kind of go over it. I still consider him a good friend though and me not liking him anymore has made being friends with him so much easier.
So. Moral of the Story. Tell him. I don't know if you have or not yet, if not formal is a good time. It'll make you feel better, whether you get him or not. I think the outcome can only be positive.