I really like this guy and when i'm around him i get all shy and tonge tied. HELP!!!!?

the guy is 1 year older than me(hes a junior and im a sopre)and he and i talk but were not really friends. im normally a little quiet or shy but when im with him i can barely get any words 2 come out hes driving me absolutely crazy! my friends dont know that i like him but i think hes starting 2 figure it out. hes not hot but hes cute and really muscular and funny he flirts with all the girls but they all think its annoying.i feel really awkward when my older sis asks who i like. i jus tell her no1 but she knows im lying. on the 1st day of school in homeroom he looked around the room and decided 2 sit by me. i couldnt look him in the face i could feel my face burning and i knew he saw it bcuz he seemed a little uncomfortable and i kno my sis saw me she kept watching us. we didnt say much which is wierd bcuz he usually wont shut up. he usually flirts with me in band and asks me 2 play like card games or something with him &his friends i just want 2 kno if he likes me or not Plz help