This world is full of teenagers doing incredible things, and they give us hope for the future. While Mexico’s Dafne Almazán is the world’s youngest psychologist and a teacher making sure other gifted kids get the education they deserve, Sweden’s Greta Thunberg has inspired a generation of students to fight for the environment with her commitment to climate change activism. In the United States, Gitanjali Rao is using her skills as an inventor to tackle Flint, Michigan’s water crisis.