Does my best guy friend like me?

This term at school in Spanish, I sat near this guy. He's really nice and funny and smart, and he's in my last class, too, so we get to talk a lot. He isn't the most popular of guys either, but he's really fun to be around. We talked more and more, and now we're really good friends. We sit next to each other in my last hour and he's always talking to me and we scoot our desks together so we can work together on assignments and stuff, and I go over to his house pretty often and we hangout. Yesterday he was watching a movie and we were talking on Facebook. He said that he was jealous of the main character (he was watching I Am Number Four) because he got the cute girl, and I suggested that he go out and get himself a cute girl, but I guess it made it kind of awkward or something, because he's under the impression that nobody could ever like him (sigh, how blind people can be.) But it's kind of depressing. I know that he likes somebody, and my sister knows who it is, but she would never tell me, and he's never said anything about her to me. All my friends say that they think he likes me, but none of them will ask him for me. Any help with this, because I'm lost.