Demi Lovato is another shining star in the Disney crew that has dominated pop culture recently. The 16-year-old Texas native has not only starred as Mitchie Torres in 'Camp Rock,' but she's also rocking out with her own solo music career. But what do you really know about this teen actress/singer? Put your knowledge to the test in this KOL quiz.

He's at the top of his pro skateboarding game, has his own clothing and footwear line, and at 18 years old, Ryan Sheckler even stars in his own TV series, 'Life of Ryan.'

His dreamy blue eyes and ramp skills are enough to make the ladies swoon, but if you really adore this California boy, then you should be able to ace this 10-question quiz about the sports star. Let's see how you score!

It's hard to listen to the radio and not hear a song by Rihanna. Whether you're rocking out to 'Umbrella' or her latest hit 'Take a Bow,' chances are you know at least one of her singles by heart. The 20-year-old is everywhere these days -- thanks to her loyal fans -- but do you really know all there is to know about Rihanna? Take this KOL quiz and find out!

Justin Timberlake seems to have his hands in everything. Not only is he a mega pop star, but he's got a budding movie career, his own clothing line and has even dabbled in the restaurant business.

Do you count yourself as a huge JT fan? Test your knowledge of the star's career in this KOL quiz and let's see how "justified" you really are.