he defo likes you but he is to shy to hold the gaze. you should defo approach him & talk to him in private...tell him that you like him. the reason I know this is that I am exactly like that guy with a girl I like.
LOL some guys have a hard time expressing themselves. I remember the one that I had a crush on would do that to me I would see him staring me down from the corner of my eye but when I look at him he turns away. I think he's being shy just wanting to check you out on the low. But its a good thing if he is looking.