I refused to wear pants until I was in 6th grade; the answer was always dresses or skirts, usually with leggings or tights (which I could pull off then, I just don't look great with them now). As soon as I discovered jeans, I sort of fell in love and distanced myself from dresses for quite a while. I can still rock a dress every so often, and lust after twirly skirts that I see at swing and contra dances garbing my friends, but on a whole, the answer is pants.
Purchased for a cool, under twenty dollars during my senior year in high school, I wore this tea-length dress with a bit of a crinoline bottom to prom. And unlike most prom dresses, it fit me gloriously, and was simple enough that it has been happily recycled for many dressy occasions, and is companion to several similar dresses in my closet (maybe I'll post some additional photos soon).
One of my favorite things about being small is that many of my favorite outfits from yesteryear still fit me quite nicely. I most recently wore this dress to my senior cinema showcase last May.