An Indiana teenager has achieved something no other student in the world achieved this spring: a perfect score on the Advanced Placement Calculus AB exam. Felix Zhang is a junior at Penn High School in Indiana. The College Board, which administers the AP exams, told the school's principal that Zhang achieved a perfect "5" rating and was the only student in the world to earn every possible point on the AP Calculus AB exam. In other words, he achieved a 108 out of 108. To read how Zhang reacted to his score, click the LINK IN BIO.