How do I let him know that I'm not out of his league?

So long story short, I've become very, very close friends with a guy I've gone to school with songs grade 7, only in the last four months because of the school play. We worked very closely together in our roles (I was his boss, he was my secretary) for three months and just became best friends during and after. So basically I've developed feelings for him, and I've detected that he may have feelings for me. Yesterday he came over to watch a movie and stayed for like, seven hours. He didn't have his car so my mom drove him home, insisting that I didn't come for the ride. Later she told me that he had confessed to having strong feelings for me, but he puts me so much higher above himself and believes that I am out of his league and unattainable (he calls me humble and nice all the time so apparently it's not my actions...) although we are both dorks, as my mom said. He also said that he wants to keep growing our friendship before trying anything because he doesn't want to lose me (which I totally support). So how do I discreetly let him know that I am not, in fact, out of his league?