Bill and Melinda Gates addressed their annual letter, which was published on Monday, to young people. They asked students to tackle climate change.
"You may be wondering what you can do to help," he wrote. "First, it’s important for everyone to get educated about this energy challenge. Many young people are already actively involved in climate and energy issues and I’m sure they could use more help.
"Your generation is one of the most globally minded in history, adept at looking at our world’s problems beyond national borders. This will be a valuable asset as we work on global solutions in the decades ahead.
"Second, if you’re someone with some crazy-sounding ideas to solve our energy challenge, the world needs you. Study extra hard in your math and sciences. You might just have the answer."
If you'd like to read the Gates' full letter, you can click here. But in the meantime, here are some of the young people who are way ahead, and already taking big steps to tackle the climate change problem.