Alex Trebek with Colin O’Grady, a teacher from Fairfax County’s West Potomac High School, during the “Jeopardy!” Teachers Tournament. (Carol Kaelson/Jeopardy Productions Inc.)

The "Jeopardy!" category was “Hard Rockers,” and host Alex Trebek read the $2,000 clue in his trademark baritone: “Girls, Girls, Girls . . . Long legs and burgundy lips . . . Girls, Girls, Girls . . . Dancin’ down on the Sunset Strip . . . Girls, Girls, Girls.”

Colin O’Grady had brushed up on his Shakespeare trivia for his appearance on the game show, and this set of lyrics took him by surprise. But as a child of the 1980s, he was still prepared to provide the question: “Who is Motley Crue?”

O’Grady, an English teacher at Fairfax County’s West Potomac High School, got it right and went on to dominate the quarterfinal round of the two-week “Jeopardy!” Teachers Tournament. He currently leads the field of educators with $21,200 in winnings and will advance to the semifinals on Wednesday.

“I’ve watched the show ever since I was a kid — I’ve always been a bit of a trivia nerd,” said O’Grady, 35.

He first tried out for the show a decade ago but didn’t pass the audition phase. He took the online quiz half a dozen times before he was selected for the Teachers Tournament, which awards a $100,000 grand prize. O’Grady credits his success to his training as a teacher.

“Trivia is just meaningless information,” O’Grady said. “It’s just stuff you’ve accumulated in your head. I think most teachers are like this, where we are constantly reading.”

A native of Orange County, Calif., O’Grady originally planned to attend law school but became enamored with his college literature courses at Stanford. He decided to pursue a career in education and joined the Fairfax County school system in 2005. To prepare for his appearance, O’Grady watched “Jeopardy!” at home, standing in front of his television with a click pen to mimic the buzzer and shouting out the questions. His voracious appetite for facts paid off.

“Teachers are by nature curious,” O’Grady said. “I call it the Wikipedia rabbit hole, where you read one thing and then another thing related to that and then a half-hour later I have no idea where I started.”

O’Grady teaches 10th- and 12th-graders and leads an elective course on the bard from Stratford-upon-Avon. Shakespeare is a frequent topic on “Jeopardy!,” so O’Grady felt confident that he’d have an advantage on the show. (During his appearance, O’Grady’s students recorded a message to the teacher and one of the teens held up a skull with the name “Yorick” scribbled on the forehead.)

In the Shakespeare elective, O’Grady has the class read the revenge tragedy “Titus Andronicus,” an especially gory play that is not very popular among high-schoolers. To get the teens more involved with the assignment, O’Grady covers his classroom with painter’s tarp to act out some of the scenes, flinging fake blood on the floors and walls.

“The whole way to teach it is to get them to play with it rather than sit in chairs and read it,” O’Grady said. “They use the blood to play the scene out the way Shakespeare wrote it.”

Alas, he has been no “Jeopardy!” categories about Shakespeare so far. But during the Double Jeopardy round, Trebek began reading clues from more contemporary forms of poetry, including songs from 1980s hair bands such as Van Halen and Guns N’ Roses.

“Those are the bands I grew up with,” O’Grady said. “It was pretty funny to hear him read the lyrics.”

O’Grady said he missed only two answers after buzzing in. One clue was a Daily Double on which he wagered $3,000: “The last king of America.” O’Grady said George II, but the correct response was George III. The other missed clue was during the Final Jeopardy round about presidential libraries, where the answer “40 Presidential Drive” should have elicited the question “Who is Ronald Reagan?” (the 40th president). But O’Grady wrote down Bill Clinton. At home in Alexandria, O’Grady said he was embarrassed about that flub.

“I’m married to a social studies teacher,” O’Grady said. “So that was a little awkward.”