A guy sitting right in front of you in class turns his head around and slightly narrows his eyes and looks at you from the corner of his eyes? He has never talked to me before or any kind of interaction...
okay, let me clarify, he turned around in his seat (I was sitting right behind him) and gave me a slightly crooked smile with his eyes almost squinting when this other guy entering our classroom said he wanted to sit by me (in a joking manner, when the teacher was assigning his seat)
i had a guy do this last semester except he turned his chair completely around and faced me. we never talked but I did get a vibe that he liked me. he probably wants you to start a convo with him. I have a guy now doing this in my summer class. He came and sit right next time me and kept rubbing his head but looking at me in the corner of his eyes. honestly he wants to say something and cant. just say "hi" and see what happens. guys are SO hard to read lol. good luck