A federal court will hold a hearing Monday in a case filed against a Missouri school district that told a lesbian student she could not attend prom with her girlfriend.

Officials at Itawamba Agricultural High School in Fulton, Mississippi had told senior Constance McMillen that she could not arrive at the prom with her girlfriend, another student at the school, and could not wear a tuxedo. They warned McMillen that she and her date might be thrown out if others were uncomfortable with them.

When the ACLU sent the school a letter demanding that the couple be permitted to attend, the school board canceled the prom for all students.

The ACLU then filed a lawsuit on McMillen’s behalf in the U.S. District Court for the Northern District of Mississippi, charging that school officials are violating her First Amendment rights to freedom of expression. They are seeking a preliminary injunction to require that the prom be held and the couple allowed to attend.

Over 385,000 people have shown support for McMillen by becoming “fans” of a Facebook page set up on her behalf. McMillen has appeared on The Wanda Sykes Show and later on The Ellen DeGeneres Show, where Ellen Degeneres presented her with a $30,000 scholarship from digital media company Tonic.com.