Please help me!! How can I show him that I like him!!!!?

I like this boy. I’m 16 and he is 17. Hes never had a girlfriend and Ive never had a boyfriend. I've heard from my best guy friend who is also his friend, that he likes me and wanted to ask me to both homecoming and prom but was way too shy to. We had english together and would talk. I've seen him with friends at lunch time, and boy is he LOUD! But in english cl, he is the quietest boy ever. Everytime I start conversation, he seems surprised, and struggles to think of something to say back to me. But once he does, we could talk for forever! He used to blush, but not recently. My heart tells me he likes me the same way I like him, but my mind is over thinking it all. I am so scared that I am making a fool out of myself. I am super shy with boys I like. God he is just such a cool person. Summer started and on the last day, all I said was a smile and bye and he said bye back and smiled. I hate myself now for not saying anything more than that. And now I'm sad because I wont get to see him till senior year! So I wrote on his wall saying that I hope we have cles together. He hasnt been on facebook for 3 days so he hasnt seen it yet, Hes not much a facebooker as I am :P His little sisters bestfriend told me they've been having family problems and that maybe that is why he doesnt make a move on me bcuz he is embaressed/doesnt wanna bring me into tht? I'm not sure...Should I just move on w/ myself, enjoy summer, and stop acting like a dumb girl? I know this seems like a crush, but its different....its the weirdest feeling of my life...what should i do???? I have no way of contacting him other than facebook, and I dont wanna feel like a creep...