High-schoolers are some of the loudest champions of a bill seeking to ban the use of disposable foam containers.

Shannon Murphy, 16, and a dozen other high school students crammed into an overflowing hearing room earlier this month at the state Capitol to support the ban.

It was Murphy’s first time testifying before state lawmakers, and she had an audience of more than 300 individuals, including many environmental organizations and food vendors, when she voiced her concerns about the damage polystyrene foam containers are having on the environment.

Senate Bill 1109 SD 1, the bill Murphy testified in support of, seeks to prohibit the use of polystyrene foam containers by food vendors, starting in 2020. The material is commonly used for coffee cups and takeout containers. The measure moved through the Senate Feb. 15 when it passed a second reading.

“This is something that really matters to me, and I really want to make a difference,” she said, recalling how picking up trash on the beach inspired her to encourage lawmakers to ban the material. “I would see pieces of Styrofoam in my sifter, and the wind would just pick it up and blow it out because it is so lightweight.”

Murphy, a junior at Kaiser High School and vice president of a beach cleanup club called Wipeout Crew, was allowed to miss class to testify.

“I am here, speaking out to all of you, because this is my future — to the point where this issue is more important than school right now,” Murphy said in her testimony. “I don’t want to worry about my kids one day playing on the sand and being surrounded by nothing but debris.”

The last time the bill moved as far as a second hearing was 2008.

Rafael Bergstrom, Surf-rider Oahu chapter coordinator, said he was surprised by the large crowd.

“I knew people were engaged, but to see that number,” he said, “I never could have imagined that. … Here’s a hearing at 1:15 p.m., in the middle of the day. People cared so much that they flooded into a hearing room.”

Some 321 individuals as well as environmental organizations and food vendors testified in support of the bill Feb. 8.

Those opposed, including the Hawaii Food Industry Association, have said the ban would increase costs for consumers and hurt mom-and-pop restaurants.

Kaiser High teacher Paul Balazs said that by testifying, his students were able to get a real-life experience they wouldn’t in the classroom.

“Through (testifying) kids are developing creativity, developing critical thinking, developing resiliency, self-confidence, grit,” he said. “These aren’t easily taught in a classroom — not in a way that’s true to life, anyway.”