After graduating high school in Australia, actor Hugh Jackman spent a gap year working as a P.E. teacher and English and drama tutor at the Uppingham School in London, England. While walking the red carpet at a film festival in 2013, Jackman recognized one of his former students working as an entertainment reporter and asked him about the progress of his physical education.

In 1991, J.K. Rowling moved to Porto, Portugal, to teach English as a foreign language for two years. She taught at night, and during the day, she began writing the first chapters of the first Harry Potter book. Today, Harry Potter is the best-selling book series in history.

After graduating from NYU, comedian and actor Billy Crystal worked as a substitute teacher on Long Island while performing comedy at night in New York City, home to some of the country's top bucket-list landmarks.

Before becoming a rock 'n' roll icon, KISS frontman Gene Simmons worked briefly as a sixth grade teacher in New York City's Upper West Side. "I discovered the real reason I wanted to be a teacher," he told the Lakeland Ledger in 1978. "It was because I wanted to get up on stage and have people notice me. I had to quit because the stage was too small. Forty people wasn't enough, I wanted 40,000."

After graduating from Harvard Law School, former President Barack Obama taught constitutional law and race theory for 12 years at the University of Chicago Law School. During this time, he began his political career by being elected to the Illinois State Senate.

Barack Obama is one of many former presidents with teaching backgrounds — John Adams, Woodrow Wilson and others worked in academics. Lyndon B. Johnson taught Mexican-American children at the segregated Welhausen School in South Texas for nine months and later taught public speaking at Sam Houston High School in Houston before entering politics. His experience at Welhausen helped informed his "Great Society" political agenda.

Grammy-winning musician Sheryl Crow's first job after college was working as a music teacher in an elementary school in St. Louis. She moved to Los Angeles and worked as a backup singer before making it big.

Best-selling "Da Vinci Code" author Dan Brown graduated from Amherst College and then taught English and Spanish at Beverly Hills Preparatory School in Los Angeles and his alma mater Phillips Exeter Academy in New Hampshire. He quit teaching in 1996 to become a full-time writer.

Puerto Rican-American "Hamilton" creator Lin-Manuel Miranda worked as an English teacher at his old high school, Hunter College High School in Manhattan while writing his first musical, “In The Heights.”

Before he was "The A-Team" icon Mr. T, Laurence Tureaud worked as a gym teacher at the Paul Laurence Dunbar Vocational Career Academy as well as a bouncer and bodyguard in Chicago. He was discovered by Sylvester Stallone, who saw him in an "America's Toughest Bouncer" competition and offered him a part in "Rocky III."

Speaking of “the Italian Stallion,” Sylvester Stallone himself also worked as a teacher. Stallone worked as a gym teacher while studying drama at the American College in Switzerland, a beautiful adventure destination no matter the season. He left school before graduating, eventually moving to New York City to pursue acting.

While he's famous for playing a sheriff and an attorney on TV, Andy Griffith taught high school music and drama in North Carolina for three years before moving to New York City and breaking into the entertainment industry.

After graduating from Yale Law School and passing the bar exam, Hillary Rodham followed her then-boyfriend Bill Clinton to Fayetteville, Arkansas, where she taught criminal law at the University of Arkansas, Fayetteville's law school.

Irish actor Liam Neeson's two sisters are teachers, and the "Taken" star began pursuing that path as well, attending teacher training college for two years in Newcastle upon Tyne, England. His teaching career ended when a 15-year-old student pulled a knife on him and he responded by punching the student in the face. Though he was acting in self-defense, he was fired and began pursuing acting instead. Perhaps his action-star moves were proof he wasn't meant to live a peaceful life as an educator.

After graduating from the University of Maine, acclaimed horror writer Stephen King got his teaching certificate and worked at Hampden Academy in Hampden, Maine, before publishing his first novel, "Carrie."

Before his music career, Sting studied at Northern Counties College of Education and worked as a teacher in Cramlington, England, for two years. He then moved to London and formed his band, the Police.

"Grey's Anatomy" actor Jesse Williams worked as a teacher in Philadelphia public schools for six years after college, teaching American studies, African studies and English.

After graduating from Howard University, Grammy-winning singer Roberta Flack got a job teaching music and English in Farmville, North Carolina. She then moved to Washington, D.C., and continued teaching junior high and piano while playing music gigs at night.

After serving in the U.S. Army, actor and singer-songwriter Kris Kristofferson almost became a teacher. He turned down an assignment to teach English literature at West Point, instead moving to Nashville, Tennessee, to pursue a music career.

After graduating college, Bill O'Reilly taught English and history at Monsignor Pace High School in Miami, Florida, for two years. He then got his master’s and began working as a journalist.

Apple co-founder Steve Wozniak actually pursued teaching after leaving the computer company in 1985. He finally completed his degree at UC Berkeley in 1986 and then began teaching computer classes in California to fifth- through ninth-graders. While we applaud "Woz" and the others on this list for sharing their knowledge with students, perhaps they should take some time to educate their fellow celebrities, many of whom have a habit of famously misusing words.

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