Teens at Plano Senior High School in Texas are trying to redefine beauty, rallying students to wear no makeup Friday - an initiative they're calling "Operation Beautiful."

"I just really began to see how I don't need makeup to be beautiful," said Madeline Milby, 17, vice president of the student congress and a senior at PSHS, which is in the Dallas suburbs. "There's so much more to me. It's your personality, your passion and what's inside your heart."

Plano Senior High is a school with 2,500 11 th and 12 th graders. Milby said she would spend up to an hour and fifteen minutes getting ready for school, putting on makeup and styling her hair. It turned out that a majority of the girls at her school were doing the same. That jump-started the idea of "no makeup day" at PSHS.

"A while back we heard of a school doing this before, and we thought it'd be a really cool idea to bring it to our school," Milby told ABC News. "The goal for this project is to promote inner beauty and to let girls know it's not about what's on the outside but about what's on the inside, and that's what makes you beautiful."

Last semester, Milby, along with senior class president Binna Kim and student congress president Monica Plenger, came up with the idea to get all girls at the school to have one day without makeup.

"I think there's pressure for girls to look a certain way, to meet a standard. The standard is being pushed through media and magazines and everything," said Milby. "I'm really hoping it'll make the girls at school feel more comfortable and see that they're beautiful without makeup and they don't need to use makeup to cover up themselves."

To get the word out and gain support for "no makeup day," the three best friends and other classmates created a YouTube video explaining the mindset behind "Operation Beautiful." Teachers showed the video in their classrooms at school.

"We just really want to focus on, not that makeup isn't a bad thing, we're not trying to say that, you know, don't wear makeup ever again," says Kim in the video. "What we really want to do on this day is to prioritize bettering yourself on the inside rather than bettering yourself on the outside."

In the video, girls who attend PSHS confess they spend up to an hour and a half getting ready for school while boys say they spend only five minutes.

"We challenge you this Friday, March 8, to not wear makeup and support Operation Beautiful," say subtitles at the end of the video.

While there has mostly been a positive response from girls and boys at PSHS, they've heard some negative feedback. Still, Milby said she hopes that all students learn from Operation Beauty apart from their position.

"Guys are in shock. They really are starting to realize how much pressure there is on girls," said Milby. "We're all seniors, but we're hoping about making it a recurring event at school."

As one male student put it in the Youtube video by quoting teen sensation One Direction, "You don't need makeup to cover up, because being the way that you are is enough."