Instead of letting a lesbian couple go to the prom, a Mississippi school opted to cancel the dance altogether. Now the American Civil Liberties Union is stepping in on behalf of 18-year-old Constance McMillen.

McMillen never expected the school to react as it did. Afterall, the April 2nd prom is only days away and so much money had already been spent. But when the ACLU demanded that officials change a discriminatory policy banning same-sex prom dates, the school went ahead and called off the prom.

The high school student was reluctant to go back to the high school after the decision, but her father told her she needed to face her classmates.

"My daddy told me that I needed to show them that I'm still proud of who I am," McMillen told The Associated Press in a telephone interview. "The fact that this will help people later on, that's what's helping me to go on."

But some students didn’t hide their disdain. "Somebody said, 'Thanks for ruining my senior year,'" McMillen said.

In response to the district’s decision, the ACLU filed a lawsuit on behalf of Constance, seeking that the court order the school to hold the prom, allowed Constance to escort her girlfriend, who is a fellow student, and wear a tuxedo, which the school said also violated policy.

McMillen says she hopes her fight will make it easier for gay students at other schools facing discrimination.

"I want other kids to know that's it not right for schools to do that," she said on CBS's "The Early Show."

This is not the first time gay students have been at odds with school policy:

• In October we told you about a lesbian in her senior year in high school whose school refused to publish her senior photo in the yearbook because she wore a tux instead of the traditional drapes.
• In 2002, a gay student sued his school district in Toronto to allow him to attend a prom with his boyfriend. A judge later forced the district to allow the couple to attend and stopped the district from canceling the prom.

U.S. Rep. Jared Polis, of Colorado, has introduced a bill to Congress that would make it illegal to discriminate against gay and lesbian school students. He said at least 10 states have such laws, and his bill is modeled after those.

"This situation with the prom is a perfect example of why we need to protect students from discrimination. In this case it's a prom. It other cases, it's getting beaten up or killed," Polis said.

What can you do?

As you prepare for prom season, learn your rights and share them with your classmates!