Could it be?

I have known this guy for about a year. He is in my world history class. I actually was friends with one of the people in the group he ate lunch with and they accepted me. For the first 2 months that I knew him we have exchanged glances and hellos. I finally got up the courage to talk to him. For the last 5 months I have been talking to him, as in full conversations about everything. I have grown to really like him. He seems to be a very polite, sweet, and caring guy. We sit together at lunch and walk to class together. I have glanced at him occasionally and he seems to be, not checking me out but analyzing me. I am an extremely analytical person and every time I see him in the halls at school he always tries to get my attention (he doesn’t know I already know he’s there) I do say hi. The problem is though, that he may not like me the way I like him. What I am thinking is flirting may be just friendliness. How can I tell if he like likes me. Also, if he might like me, should I tell him my feeling or should I wait for him to say some thing?