Grr, please help! What's this guy problem?!?

Okay this dude is starting to freak me out! First we have never really talked except for a few days ago when he bumped into me and I said sorry, other than a few hi's, that's it. Then there is the constant staring! Oh my god! He stares so much, he will just turn around in the middle of a test and look right at me with no expression on his face. There was one day a few weeks ago when he barely did any work on his test just to turn back and look back. Then what is weird is that when he is around me he is clumsy, then in homeroom he will be okay talking to any girl or boy and just be fine doing what he's doing. So, what do you think is up??? Also in Math today my friend and I were singing song parody's and cracking jokes, when I looked at the clock I saw that he was looking right at me, while his friend was trying to talk to him. Also we are in High school. Also is homeroom he will hang out around my desk and awkwardly stand there, then find another person to talk with. But then a week ago I sent him a friend request and he hasn't accepted, and I checked to sse if he has denied the request and it said pending friendship. Also one day one of my guy friends came up to me and is all like whats up, so I said hi, then he turned to him and said hah, she talked to me! So, what is his deal?