1. Simone Biles
Simone Biles, born in 1997, is an American artistic gymnast who won five medals (four gold, one bronze) at the 2016 Olympics in Rio de Janeiro, Brazil. She began training at the tender age of six and had this to say after becoming an Olympic legend, "I'm not the next Usain Bolt or Michael Phelps. I'm the first Simone Biles."
2. Malala Yousafzai
Malala was still a young girl when she wrote an anonymous diary about Taliban rule in her home country of Pakistan. Standing up for girls' rights to education, she was shot in the head and recovered, going on to become the youngest person ever to win the Nobel Peace Prize. She is currently studying for her A Level exams in Britain, and hopes to study at Oxford.
3. Michael “Prince” Jackson Jr.
Michael Jackson Jr. is the first son of the King of Pop. Born in February 1997, his dream was to become a producer and director one day, and Jackson recently launched his own company King's Son Productions. However, when asked if he was going to pursue a career in music and dance himself, he admitted to L.A. Times that he cannot do either.
4. Madison Kocian
Madison is another famous US gymnast. She won an Olympic team gold medal in Rio, as well as a silver on the uneven bars. In an interview with Inside Gymnastics magazine, she counted "sharing laughs in our little apartment in the Olympic village" as one of her fondest memories of competing in the Olympics.
5. Kylie Jenner
Kylie is part of the Kardashian/Jenner celebrity family, and the face of her own line of Kylie Cosmetics. She has over 90 million followers on Instagram and once used her popularity to launch an anti-bullying campaign - #IAmMoreThan - to shed light on this serious issue.
6. Katie Ledecky
Katie Ledecky was the youngest member of the US swimming team at the 2016 Rio Olympics, but that didn't stop her from winning four gold medals and one silver at the games.
7. Chloe Grace Moretz
American actress Chloe Grace Moretz began her career at the tender age of seven and is best known for Carrie White in Carrie, Mia Hall in If I Stay, and Cassie Sullivan in The 5th Wave. Chloe also campaigned on behalf of Hillary Clinton in the 2016 presidential election.
8. Maisie Williams
British actress Maisie Williams is most well-known for playing Arya Stark, the headstrong younger daughter of House Stark in the HBO series, Game of Thrones. According to The Hollywood Reporter, Williams will be joining her on-screen elder sister Sophoe Turner, who plays Sansa Stark, in the X-Men franchise as Wolfsbane, a mutant that can turn into a wolf in New Mutants.
9. Asa Butterfield
Also from England, Butterfield began acting at eight. When he was 10 years old he starred in The Boy in the Striped Pajamas, and won a number of nominations for that role. Since then, he has had successful title roles in films such as Ender’s Game (2013) and Hugo (2011). He turned 20 this February.
10. Camila Cabello
Singer-songwriter Camila Cabello began her career auditioning for music competition reality show, The X Factor, in 2012. After being eliminated, she was brought back along with four other contestants to form girl group Fifth Harmony. They released an EP and two studio albums together before Cabello announced her departure from the group in December 2016.
11. Bella Thorne
Known for her flashy red hair, Thorne got her start on Disney TV show, Shake It Up. What you may not know is she's actually not a natural redhead but a blonde. Her next big project is TV show Famous in Love, about a young college girl who suddenly becomes famous after being cast in a movie.
12. Cody Simpson
Australian-born Simpson started out from humble beginnings on his own YouTube channel. He creates music with a unique vibe, and his second album Surfer's Paradise reached number ten on US Billboard 200. He said in an interview with AXS that social causes and environmental issues are what currently inspires his writing.
13. Nash Grier
American Internet personality Nash Grier started posting to Vine in early 2013 and now has over 12 million followers. With his unique sense of humour and ever-increasing popularity, he has opted not to attend college yet. But when asked by Huffington Post what conventional job he would take, he answered either a doctor or marine biologist.
14. Jacob Whitesides
American singer-songwriter Jacob Whitesides is another star who got his start on YouTube. At the beginning of his career, he would set alarms to wake himself up so he could chat to fans in different time zones. With the release of his debut album Why in 2016, he continues to wow us with his dedication.
15. Zara Larsson
Singer-songwriter Zara Larsson shot to fame when she won the Swedish talent show Talang at just 10 years old. Her debut album So Good was released earlier this year to resounding sucess. When asked by Vogue what three things she would save from her house in a fire, she replied, "childhood photo album, family, computer". Sounds about right.
American rapper Sidney Royel Selby III is best known by his stage name, Desiigner. He shot to fame in 2016 with the release of his debut single Panda, and in the same year he signed with Kanye West’s GOOD Music imprint under the backing of Def Jam Recordings. He turned 20 this May.
17. Becky G
Rebecca Marie Gomez, who goes by stage name Becky G, is a Mexican-American singer and songwriter, who’s also displayed exceptional rapping skills in several performances. She started small by posting videos of remixes of popular songs on her YouTube channel and then had breakout hit Shower in 2014. Becky G has also branched out into film roles, playing the Yellow Ranger in the live-action Power Rangers movie earlier this year.
18. Olivia Holt
A popular teen icon, Holt acted in two notable Disney shows, Kickin’ It and I Didn’t Do It, before branching out into music with her debut album Olivia in 2016. She's the latest in a long line of female Disney stars that went on to further success; a list that includes Hilary Duff, Miley Cyrus, Selena Gomez, and Demi Lovato.
19. Isabelle Fuhrman
Fuhrman played the sadistic tribute Clove from District 2 in The Hunger Games (2012). In an interview with Seventeen magazine, she revealed she did all her own stunts in that movie and had to train in combat and knife throwing. Talk about getting into character!
20. Rebecca Black
Rebecca Black gained fame with her song Friday in 2011. (Is it in your head now? Sorry.) But not the good kind of fame - the music video has garnered over 2.6 million dislikes on YouTube, but her follow-up Saturday released in late 2013 with Dave Days was better received. She is also active on YouTube and posts videos on music, style and beauty. Most recently, she released a single called Foolish on April 21, 2017. She turns 20 in June.