17 Most Powerful Stars Under 21 By Author Alana Altmann at Jan 28, 2014 • Category Abigail Breslin Seventeen Magazine counts down 17 most powerful girls under 21. 1Selena Gomez: The Mogul Fashion icon, clothing designer, superstar singer, social media powerhouse — Selena’s entering mogul territory. 2Demi Lovato: The Cool Chick The cool best friend we all wish we had… and an awesome singer to boot!3Miley Cyrus: The RebelMiley Cyrus was EVERYWHERE this past year. Everywhere. Love her or leave her, she’s making powerful waves. 4Victoria Justice: The Philanthropist This young star is making a difference. 5Chloe Moretz: The BodyguardChloe, one of Hollywood’s hottest young actresses, has discussed the bullying her two gay brothers dealt with growing up. 6Karlie Kloss: The Model on a Mission Karlie’s not just another gorgeous face. Karlie’s Kookies, her cookie line, supports FEED’s mission to feed the hungry. 7Gabby Douglas: The Champion Olympian and best selling author? Go, Gabby!8Lorde: The BadassAll hail Lorde, the coolest queen bee in music. 9Cara Delevingne: The Free SpiritSupermodel Cara’s stand-out features and fun personality make for a winning combo. 10Ariana Grande: The Social SuperstarA voice like Mariah’s and hit show? Ariana is definitely a powerful young star. 11Kate Upton: The Cover Girl Everyone’s favorite bombshell has graced countless covers this past year. 12Ariel Winter: The Brave OneAriel is one of the best parts of Modern Family, and she dealt with public family issues with grace.13Abigail Breslin: The VeteranThis child star turned teen acting dynamo can hold her own next to Meryl Streep and Julia Roberts!14Carly Rose Sonenclar: The VoiceThe X-Factor finalist has vocals and heart. 15Ashley Rickards: The ActivistThis Awkward star was a participant in the Live Below the Line Campaign.16Zendaya Coleman: The Triple Threat Zendaya can dance (she rocked DWTS), sing, and act. 17Bridgit Mendler: The Rising StarThe multi-talented Good Luck Charlie beauty is making a household name for herself.