Rooster Under the Table by Lois June Wickstrom and Jean Lorrah
Once upon a time, in a land of magic, there lived a princess who did NOT want to marry. She wanted to have adventures like the knights, or rule a kingdom like her father. She didn't like sitting around in pretty dresses, eating daintily with fancy silverware, and speaking in a soft, ladylike voice. And those were the only things a queen, ever got to do.
This is not your classic folktale princess.