Although this prolific and perky player had been in the business for most of her life, she became an instant teen idol in Disney's wildly popular 2006 TV-movie High School Musical. Discovered in a New Jersey mall at age 3, Tisdale appeared in over 100 national commercials and stage productions before launching her small-screen career with a string of guest spots on youth-oriented series (7th Heaven, Charmed). In 2005, Tisdale became part of the Disney star-making factory when she signed on as the babysitter to the title twins on The Suite Life of Zack & Cody. But she made history — and forged her name — as one of the stars of High School Musical by becoming the first female artist to debut two singles simultaneously on the Billboard Hot 100 Chart.