The college I went to had a pretty big dance school. Every year they posted information about when and where the Disney dance auditions were being held. I was in Oklahoma City at the time, but I think the students usually had to travel to Dallas (if I remember right) for the auditions. Disney usually only hires people on a yearly basis, but I believe that there is also a summer program for dance/theater people. I know my cousins worked at Epcot running lights for a summer.
I found this information in the Disney careers section:
Please call the audition hotline for specific details at (407) 397-3220, Monday-Friday, 10 a.m.- 5 p.m., except holidays.
Disney Auditions
P.O. Box 10000
Lake Buena Vista, FL 32830-1000
The calendar online only listed dates for November, so she would probably need to call and get a schedule. If I remember right from friends who auditioned, the spring was when a lot of them happened. I would recommend calling or writing soon as she will probably have to travel for the auditions.
Hope this helps and I wish her the best of luck. Everyone I know who got summer roles at WDW had a blast!