Is he trying to ask me out? ?

I'm a 15 year. old girl, i attend a highschool. Theirs a boy who i known for a while, and we're friends but don't communicate anymore. I see him in the hallways glaring at me and looking at me constantly. This has been going on for months now. His eyes sparkle and looks thrilled to see me like he's ready to say something. On halloween theirs a guy in a mask standing still on the hallways moving his arms and trying to scare me, he doesn't do this to any other girl from what i know of. Whenever he's with a group of friends he smiles, laughes, and the friend(s) look at him like they know something i don't. He has actually had times where he had said "hi" to me, and i didn't respond, but at the moment, he was with a friend and i was the only one in the hallway. I look back at him to see if they were talking about me, i looked once again didn't say anything, then they started whispering to eachother and smurking once again. I then, went away to my next cl. Also, one time around the same moment on a different day he looked at me ,smiling with his eyes, it seemed unusual for him, to have that reaction. His arms were wobbling, and moving like as he were a octopus, and he was smiling, he was looking directly at me, as if he were going to give me a long, warm hug, and show his feeling towards me with a hug, saying he misses me and more..... I went the other direction to my cl, i was the only one in the hallway aside from him. I had to break the eye contact before he did. A couple days after that, i was walking up the stairs, i saw him/girl talking to him (tall, blonde, high-maintanance, self conceided) his whole body was facing my direction, looking at me again straight in the eye, and nodding his head as if he were listening, to her instead, he was looking at me. Then, i headed off to my clroom, There has been plenty of other incidents where he tried to get my attention by singling me out, in a large crowd. While i was walking up the stair, right ahead on the far side of the hallway, i see two guys, looking at me, the guy i ume likes me, says something to his guy friend, and he screams in a playful voice "STAlKER" and again, i look at them, and was walking there direction, and they were like " oh no, she saw us, and then scrambled into the guys restroom. The only area that i was heading from the begginning was to cl. Next, thing i know it i'm late for cl, i'm sure they were late also. Out of everyone on the crowd. He doesn't really give a reaction when he's around anyone else except when he's with his guy friends, when they look at me like, they have something to hide. The most recent one that i recall was when i was talking to a girl on the hallway, barely anyone was their, in the corner of my eye i see a guy, smilling and looking as if he were about to say something, then as soon as i know it, some other guy approached the girl i'm with and talks to her, his face was unforgettable, his eyes were looking back at forth at his locker and then towards the guy, and looked as if, he were going to smash it, instead he closed it softly, and left. I then proceeded on to class almost when the bell rang. Does any of this mean anything, does he have something he's hiding from me? What do all these signs mean?