Kaitlynn Wagner, 13, and Samantha Savich, 11, were also charged with petty theft Friday, WBBH-TV in Fort Myers reported.
Investigators said the two, both students at Port Charlotte Middle School, sneaked into Neil Armstrong Elementary School Sept. 17. They were reported missing by their families.
The girls allegedly spent the night at the school snacking on food they found, making prank calls to teachers and using school computers.
A custodian went to the school about 5:30 a.m. Sept. 18 after getting a call from a security company. He found Samantha's father outside looking for his daughter, who had called someone asking for a ride home.
The girls were arrested Friday and released into the custody of their parents.