Should I ask this girl to prom?

As it is nearing the end of my senior year, prom is quickly approaching, and it is time for me to find someone to ask to prom. I just met the girl that I am considering asking in the fall of this year when we were both involved in the same club. However, that has been over since this february, so I have not been able to talk to her as often. We get along well and tease each other often, and she always says hi to me when she pes me in the hallway. We still talk occasionally when we have the opportunity, but I am not sure if she likes me or not. Also, she is a junior, and since prom is only for seniors and their dates, it may be awkward for her since she will not know as many people. However, I really like her, and I would like to go with her, but if it would be weird for me to ask when I haven't known her for very long, or if it would be awkward for her, I could look for someone else. Also, do I have to do something elaborate or creative to ask her, or could I just be straightforward and do it in person? Any advice would be greatly appreciated. Thanks!