A recent survey of more than 6,000 middle and high school students in the United States found that a majority of gay, lesbian, bisexual, and transgender students surveyed said they experienced harassment at school in the past year.

Often, harassment comes in homophobic remarks, which is why The Ad Council of America has teamed up with the Gay, Lesbian and Straight Education Network to try and change students' vocabulary, or at least make them more conscious of it.

Commercial ad "Are you going out tonight? I can't. My parents say I have to be home right after work.  Ugh, that's so gay."

These commercials are part of a campaign to teach young people to think before they speak.

Nine out of 10 students who identified as gay, lesbian, bisexual or transgender said they were harassed at school in the last year, according to The Gay, Lesbian and Straight Education Network, which focuses on the safety of all students.

Vance Smith

Vance Smith attended a small, conservative high school in the western state of Colorado. By the time he hit puberty, he knew he was gay, but he was not comfortable being open about it.

"Like I didn't change in the locker room because when I did try there would be comments for me," Smith said. "So I ended up like changing in the boiler room."

Because of stories like Smith's, The Ad Council of America started a media campaign to raise awareness about the impact of anti-gay language. The campaign uses radio, TV, newspapers, and the Internet to reach students and adults.

Priscilla Natkins

Priscilla Natkins is Executive Vice President at The Ad Council. She says anti-gay language used by teens is usually not meant to be harmful.

"What kids don't realize, when they harass, or use these phrases that they think they're innocent, they're benign, they're part of their vernacular, that their words have power and a sting," she said.

Smith is now studying modern dance at The New School in New York.

He says he no longer feels harassed, and is open about his sexuality. But he hopes other students will not have the same experiences he did. So he works with the Gay, Lesbian and Straight Education Network to help teens feel safe enough to express their sexual orientation.

He says the ad campaign is a good step.

"So if it just draws attention, and people are able to be like, 'that's so gay', and then kind of stop themselves, and be like, 'you know what, maybe I shouldn't say that', then just that clicking in their head, and them being like, maybe it's not okay to say that, is enough for me," he said.

The ad campaign's Web site gives definitions of words like "gay" so teens will know the meaning of words they use. It also encourages visitors to contribute words that can be used as substitutes.