Selena and Demi: Prom Crashers!

Break out the corsages and turn up the tunes -- Selena Gomez finally got to experience a real prom!

The Disney star, 16, attended the premiere of "Princess Protection Program" on Thursday night. Afterward, Gomez snuck out of her own premiere party and strolled around a complex in Toronto before stumbling upon the prom for Eiobicoke Collegiate Institute prom. Selena asked the security guard if she could check it out, and then surprised a group of girls at the prom by dancing with them!

"They were all dancing in a group and having fun," a prom witness dished to People magazine. "Selena was thrilled to see firsthand what a real prom is like and that her dress was much like the other girl's dresses."

Selena returned to the after-party for "Princess Protection Program" and convinced her best friend and co-star, Demi Lovato, to join her at the prom. The girls, along with a few friends, returned to the dance until 11 PM, when they were asked to leave because they weren't students.