Loudoun County boy scores perfect on AP Calculus test

A Loudon County boy is one of only 12 people in the world to take the AP Calculus AB exam without making a single mistake.

Landon Labuskes, of Aldie, Virginia, earned a perfect score on the 2015 exam. He took the test as a sophomore at Paul VI Catholic High School in Fairfax.

AP exams are based on a 5-point scale, where a 5 is equivalent to a grade of A in the corresponding college course. Landon received the top score of 5.

Of the approximately 4.5 million AP exams taken by 2.5 million high school students in 2015, only 322 students earned every point possible on an AP exam, according to a press release from Paul VI.

Labuskes' accomplishment caught the eye of President Obama, who tweeted a message of support and praise on February 11: