Does this boy like me or his he takin the piss?

well this has been going on for ages now. before i explain.....he has a girlfriend who he has been dating on and off since yr 7)this guy that i kinda like has been making passes at me from year 9 ( i am now in yr 11). at first i just thought that he was being nice to me...but then my friends pointed out to me that he might like me. i only clocked in year 10 that he might like me. he winked at me alot, he would stare at me until i smiled and looked away, he made kissy faces at me, make me laugh and annoy me regularly. then as time progresses, whenever he stood next to me, he would be really close to me, he would tell me that i am funny when ever i sed something and he was in earshot. and there was one time when he touched my arm, my chin and my face. and there was another time that he was sitting next to me and because i am left handed and he is right, we kept on bumping hands and he wouldn't move his when it was touching mine. then this week, he complemented me on my hair, he slapped my bum and denied it whilst smiling and said that he loved me( but it was casual and out of context). then yesterday he came up behind me and put his arms around my waist and didn't say anything or move them when i sed 'why are u doing that'. this was in front of his GF aswell. she was the one who pulled him away. every time he passes me he either smiles, high fives me or nods.........i have been thinking about him all the time and i was going to ask him why he was acting this way but i wasn't sure if he liked me so i didn't want to look desperate if he denied it. my friend sed that i should confront him about it. my friend also sed that he really wants to break up with her but she always gets him back.....i think it cz he likes her,but as a friend and doesn't want to hurt her feelings...what should i do...it is half term...i dnt have his number or anything and i was thinking of confronting him alone when we go back to school in a week...what do u think?? :S and please be honest........