I know that he likes me and I like him, but he doesn't know that I know or that I like him?

First off, high school drama, I know. I just graduated and I am 18, and I know that one of my best friends and I have feelings for each other (he, too, is 18 and just graduated). I've liked him for about a month or so, and we really have only been friends for about 5 months and have spent so much time together that we're super close now. He kinda always gave indications that he liked me, but nothing outward because he did have a girlfriend and so I decided to put it out of my mind. However when we were just hanging out he told me and my family that he was planning on breaking up with his girlfriend soon because they just wanted such different things. Still, I decided to keep quiet because he still had a girlfriend. But my mom spoke to him in private, had him admit that he likes me but sees me as being way out of his league. So, yesterday he told me that he had broken up with his girlfriend the day before. Again, I remained quiet about my feelings because he was freshly out of a committed relationship. So I don't want to be outward with my feelings because I want to respect him and his now ex-girlfriend and not rush anything, but I still need to let him know that I am interested and that I am not out of his league... What should I do?