Does he like her or just friends?

hey so i was at a basketball game tonight at my school and the guy that i like was there and he saw me and i smiled and stuff so we were doing good. then like twenty minutes later i saw him and he was acrossed the gym sittin on the bleachers with his arms around them (note: it was a group of guys around him but he was the only one in his row). then this girl came up and sat next to him (who is a year older then him) and sat where his arm was. he didnt move his arms but they didnt do anything. i mean they arent going out or anything and this was like the first time i have seen them together. this girl was also talking to the other guys around. so do you think he liked her since he didnt move his arms or they are just friends? plz help im going crazy over this. thanks