Just tell her that you want to talk to her..ask her for her phone number..so you can talk in private. or ask her out on a date, that way her friends won't be around. It probably would be a little awkward if you just walked up and joined in there cnnversation. Do you know the whole group? if so, it wouldn't be so "weird " for you or them. u know what i mean? But best of luck to you. I know i don't have the best advice, but I hope maybe it'll help. Let me know how it turns out.