How can I tell?

So I've known this guy since 6th grade and now we are freshman and I never really liked him until now and now I really like him and I can't tell if he likes me. We have this weird friendship thing where we like make faces at each other and say thing like "ehh" when we see each other and (I know this is extremely childish but) we will like stick our toungs out at each other. And act like we kinda hate each other but it's kinda jokingly. I can't tell if he likes me and I really like him. Any advice?