Need tips/advice

This girl at my school, who I have fallen for deeply. She has the most attractive personality and beauty ive seen in a girl at my school, She is not like those stuck up, mean girls. What she has is extreme inner beauty. But the thing is she has a boy friend BUT she flirts with me constantly and almost to the point where it would be questionable if her boyfriend found out. For ex, she touches me in a playfull manner, always gets really close to me, and sometimes even grabs my arm when we are walking and wont let it go : ). Also, during lunch( we drive out to a fast food place) she will always sit next or by me and sometimes put food in my mouth when im not paying attention. She will also poke me in the side or try to tickle me : ). Ive also heard her say on occasion that im "great" or when we come back from lunch and i decide to walk wiht her she will say "yay" or something like that. Also, she will always mock me or make fun of me in a joking manner, and she is always laughing at the stuff i say or around me when we hang out. But what i really want to know is this real or just playfullness. Im am kinda confused, and would appreciate any tips or advice. Thanks

Women. They make the highs higher and the lows more frequent.

But, by what you say, she seems to be into you. Perhaps you should just ask her what's up?

She likes you but what kinda woman would flirt with a guy while she has a boyfriend
think about that...would she do the same thing to other guys if you started to go out with her