Fifteen Jefferson High School students are facing criminal charges over a senior prank.

Six of the students are charged as adults with destruction of property and conspiracy, each of which carries a maximum jail sentence of up to a year. They also face up to six months in jail if convicted of criminal trespassing.

Nine others are charged as juveniles.

Police say that besides pulling 600 desks into the hallways and scratching the floors, the students hid dozens of telephones and calculators in the ceiling tiles on March 30. The students also allegedly wrote inappropriate messages in Spanish on a chalkboard and burned a grade book in a microwave.

All of the students were previously suspended for ten days.

Last month, parents and students held a demonstration urging the school board not to pursue criminal charges against the students, many of whom are honor students.

Parents of two of the students involved declined to comment on the charges.