Should I go talk to this girl?

Ok, so Im about to be a Senior in High School just to let ya'll know what age range im in. Anyway there's this girl I saw alot in the hallways in school this year and everytime she walked past me she would look right at me, u know, like she was checkin me out or summin? And that's a possibility since a lot girls say I look good, and I do have alot of girls comin up to me and talkin to me n all that. I'm 6'2 n play football, n i look good, so the girls like me. BUT, I don't wanna be y and ume that this girl in the hallways who always looks at me definately likes me, so I'm not sure if she does or not. Anyway Its summer time now and was just cruisin round the city on my bike, and guess who I see walkin? That girl from school. She was lookin y too, but she was all alone walkin by herself, and when I ped her on my bike, she looked at me again, the same way she use to in school. Anyway I just kept goin cuz I had stuff to do, but now I'm thinkin I shoulda stopped and talked to her, maybe gotten her numba. It's just I dunno, you think it's cool to just come up to her on the street and say hi n say "hey i seen u in school and I think u cute, can I get ya numba?" is that alrite to do? I dont wanna look like a stranger juss comin up to her n askin her for her numba, but I mean if what i think is true and she likes me then she'd prolly say yea, am I rite? What should I do? I juss think it would be a little awkward comin up to her on the street and start talkin to her outta no where. I mean if someone did that to me, it would be a little weird, but then again, if its a hot girl that did it i really wouldnt mind. so umm should I go talk to her next time I see her? O yea n i think she was a senior this year, so i proboly wont see her in school next year.