Should I ask her to be my girlfriend?

There is this girl in High school that I really like. She's really cute and is super talented. I asked her to homecoming and she said yes and we both had a great time. At a bonfire after the dance I asked her to go to the Green Bay Packer game with me and she said yes and again, we had a great time. She'll send me cute text messages and stuff but at other times she doesn't talk to me. I want to ask her to be my girlfriend but I'm a little hesitant because I still want to be friends with her without having that awkward friendship thing. Any suggestions?