Selena Gomez isn't just a superstar with an album on the charts and a hit TV show on the Disney Channel — she uses her celebrity for good. She is currently UNICEF's youngest ambassador, and for the second year in a row she is the organization's spokesperson for their Trick-or-Treat campaign, which encourages kids to raise money on Halloween to help children around the world.

Her duties as an ambassador took her to Ghana last month, where she says her life was completely changed by the experience. While there, she learned firsthand of the living conditions in the country. "I've been working with UNICEF for a while, so it was an honor to be able to travel, not because I wanted to help people but just because it was a life-changing experience to see how different people's lives are there," she told MTV News.

She went on to explain that "it was such an amazing experience" that it's made her want to travel the globe even more. "I'm addicted to it now," she said. "I love to travel to other places."

As a UNICEF ambassador, the teen star encourages other young people to get out and help, and she explained why other teens should contribute. "Not only is it a good feeling, it just makes you realize how lucky you are," she said of volunteering. "I do it all the time — I complain about the littlest things. I feel [charity work] makes you more grateful."