Boy help!! for boys mostly. but girls can answer too!!!?

Okay, so I like this boy and his name is Tim. He's in my homeroom. and he always looks at me, and i always look at him. But when I don't look at him, I still catch him staring. All of the boys in homeroom say that he told them that he liked me. I asked him out, but he said no. What's up with that?