When Flint Michigan’s water was found to be poisoning its residents, one of the people who moved into action was Mari Copeny, who was eight years old at the time. For a year and a half, state and local authorities did nothing to solve the problem. Mari wrote to then-President Obama, asking him to help her community. Obama came to Flint, visited with Copeny, and approved over $100 million to fix the infrastructure.

That was only the beginning of Mari’s activism. She’s spoken as a Youth Ambassador at a national Women’s March. She’s distributed over 500,000 bottles of water, 500 bicycles, and 17,000 backpacks filled with school supplies to the citizens of Flint. She works with the anti-bullying group Trendsetters Productions. She gets books by authors of color into the hands of local children. She initiated a letter-writing project that encouraged people to send positive messages to local children. She has even partnered with a company to produce a water filter that’s shipped all over the country. And she addressed a rally in front of the Trump White House.

About that, she said, “We need leaders that have a heart and care about everyone and not just the interests of big business and the top 10 percent... I want to see leaders actually do their job instead of sitting behind their phone and tweeting irrelevant [thoughts] and lies.”

A teenager now, Copeny busts the stereotype of kids who spend all their time on social media, sports, and parties. She is, instead, all about making the world a better place—and getting other kids involved too. “You just gotta keep speaking up and keep on using your voice. They’re going to start listening to us eventually.”