Teachers often have secret inner lives. Take a look at the educator who’s reciting Shakespeare or rehearsing math equations—he is she might be the next super-star rapper or award-winning comedian. The lesson here is to never under-estimate your teachers, you never know what hidden talents they might have!

Take a look at these top ten famous former teachers:

1. Gene Simmons – the bassist of Kiss who gained notoriety for flicking his tongue, Simmons taught sixth grade in New York City before hooking up with his band-mates. He later admitted that he got fired from his job for replacing the works of Shakespeare with Spiderman comics, which he thought the students were much more likely to actually read.

2. Mr. T – the professional wrestler, actor, and former bodyguard used to teach gym class to Chicago students back in the 1970’s. You wouldn’t argue if a Mohawk-sporting and chain-wearing gym teacher told you to drop down and give him twenty, wouldn’t you?

3. Sting – prior to becoming a superstar with the Police, Sting used to teach English, music, and soccer at a convent school. He recalls his stint as a convent teacher fondly, stating “I was the only man on the faculty. In fact, I was the only teacher not in a habit.”

4. Art Garfunkel – one half of the Simon and Garfunkel duo was really good at math. Garfunkel was a few short credits away from earning his doctorate and was teaching math at a Connecticut prep school when “Bridge Over Troubled Waters” became a chart-topping hit.

5. J.K. Rowling – the author of the “Harry Potter” series worked as an English teacher in Portugal while she was busy imagining the adventures of the student wizards.

6. Sylvester Stallone – the star of the legendary “Rocky” movies worked as gym teacher in Switzerland in the 1960’s while attending college abroad. Stallone is another phys ed teacher who you wouldn’t want to mess with!

7. Andy Griffith – the famous comedian, gospel singer, and face of the television detective Ben Matlock used to teach high school English literature.

8. Billy Crystal – the star of the “When Harry Met Sally…” worked as a substitute teacher on Long Island while struggling to land gigs. He once subbed for a girls’ gym class, which must have been an excellent source of comedic material.

9. Stephen King – the award-winning author of such horror fiction novels as “Carrie” and “The Shining” used to teach at the Hampden Academy in Maine for a cool $6,400 year.

10. Alexander Graham Bell – when you pick up your phone to make a call, you can thank Bell for his invention. The telephone pioneer got his start as a teacher at the Visible Speech at the Boston School for Deaf Mutes. He developed a strong friendship with a student named Mabel Hubbard, and when she turned 19 years old, the two were married.