How do i ask a girl to be more than just friends?

i know this is a reoccurring theme but none of the other ones fit my circumstances.
she and i are good friends, both part of the same group of friends and some of the same clubs and many of the same interests. i have asked her to the movies before but she has taken it as more of friends hanging out, because her family goes to the movies all the time, for may family we almost never go to the movies. i have even tried the meal before the movie trick. so how do i tell her that i would like to try being more than friends?