More than 250 teen activists are being hailed for launching creative campaigns to fight plastic pollution around the world—and 15 of them have been rewarded prize money for their efforts.

Last week, Bow Seat Ocean Awareness Programs (Bow Seat) announced the winners of its Marine Debris Creative Advocacy Competition, which challenged middle and high students from around the world to design and lead creative campaigns to inspire action and reduce or prevent ocean pollution.

The students working to protect the sea—and their local watersheds—hailed from the U.S., Australia, Canada, India, Nigeria, Pitcairn, Vietnam, and elsewhere.

Team Marine, an environmental club from Santa Monica High School in California, won the Competition’s Gold award and a $5,000 prize. As part of their comprehensive top-down, bottom-up campaign, Team Marine educated 800 high school freshmen about plastic pollution and successfully lobbied the school district to pass a sustainability plan that ensures support for integrating environmental literacy and stewardship into the school curriculum.

Team Marine’s campaign culminated in a giant public art installation—made out of 600 plastic water bottles—that provided a platform for the group to educate more than 400 community members about marine debris and alternatives to single-use plastics.