While we've put together a pretty thorough list of the innovators, visionaries and agents of change we expect will have a big impact over the next 25 years, we weren't content to stop there.
There are plenty of young minds at work who didn't make our list, because they're largely unproven, but they're still doing some pretty amazing things at this early stage in their life.
These teen and preteen superstars—they're all under age 20—come from diverse backgrounds and focus on widely different fields. But they all stand on the cusp of greatness, and they're definitely worth keeping an eye on.
Jack Andraka might be young, but he could be one of the most promising cancer researchers around. While sitting in his Maryland high school biology class, he had an epiphany, which led to a rapid, inexpensive way to detect protein increases that are the early warning signs of pancreatic cancer. At an estimated cost of just 3 cents, the tests—which are similar in method to a diabetic test strip—are said to be more than 90 percent accurate.
Like Michelle Wie and Tiger Woods before her, Lucy is showing all the signs of a golf phenom long, long before she becomes eligible to join the PGA Tour. In June, she became the youngest person ever to qualify for the U.S. Women's Open. (She missed the cut when she shot a 78.) Taught by Jim McLean since she was 6, Lucy is not rushing to go pro—cutting back her pro golf schedule this year to play local events and live the life of an 11-year-old.
A computer science student who recently took a leave from Stanford to accept a Thiel Fellowship, Adithya Ganesh is also the co-inventor of IntentSense, a low-cost, intelligent bionic glove for partial-hand amputees. These days, he's looking at Big Data applications in the health-care world, building predictive analytics software that he hopes will help doctors identify and understand trends in diabetes.
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Tanishq's scientific prowess is particularly astonishing, given the breadth of his knowledge. At 8, he became the youngest person to become eligible for the honor society Phi Beta Kappa. That year, he discovered two supernovae, a solar storm and a possible exoplanet by poring through hundreds of NASA images. He has also been a TV medical correspondent for the CBS show "The Doctors." It's no wonder he is one of the youngest ever to graduate high school in the U.S. He was 10 when he graduated in June.
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Tavi Gevinson has been a star in the fashion world since she was 12 and turning heads with her fashion blog. Today, she's on her way to becoming a media mogul as founder and editor of Rookie magazine, an online fashion and feminism site aimed at teenage girls. She presented at TEDxTeen, looking at how women are depicted in pop culture—and started an acting career as well, appearing in the James Gandolfini film "Enough Said" and voicing a role on "The Simpsons."
At a time when most kids are entering their freshman year of college, Colin Carson is already a first year Ph.D. candidate at UC Berkeley's Department of Environmental Science, Policy and Management. He's already gotten his bachelor's and master's at the University of Connecticut. At Berkeley, he is focusing on ecosystems that are vulnerable to human activities, identifying the weakest links through math. Ultimately, he said, he wants to combine a Ph.D. in ecology and evolutionary biology with a degree in environmental law to launch a career in conservation science. And he wants that done by the time he's 22.
When she was just 10, Talia Leman showed a knack for charitable activities, raising more than $10 million for the Hurricane Katrina foundation. She went on to found RandomKid, a nonprofit that provides resources for young people who want to make a worldwide impact on any issue. So far, the organization has worked with over 12 million people from more than 20 countries. Its benefactors have included orphans around the world and Haitian earthquake victims who needed crutches and artificial limbs.