'Ferris Bueller's Day Off' teacher ad-libbed his iconically boring economics lesson

Bueller? Bueller? Bueller?

Ben Stein was the monotone economics teacher at Ferris Bueller's high school, somehow delivering one of the most memorable scenes in the entire film.

And this weekend, as Frozen star Josh Gad bought the cast of Ferris Bueller's Day Off together for the last of his Reunited Apart webcasts, Stein, who wasn't even an actor at the time, revealed that it all came off the cuff.

“It came about after a longtime friend who was a high official at Universal and who then became head of the John Hughes Company, and he asked me if I'd like to do an off-camera reading of the role with the students in the classroom scene,” Stein told Matthew Broderick (Ferris), Alan Ruck (Cameron), Mia Sara (Sloane) and Jennifer Grey (Jeannie), who were all in on the call.

Read more: Ghostbusters cast reunite online

“I went over there, and I had a bad cold, so I'd had all kinds of cold medicine, so I was woozy. And I started reading the role off-camera, and the students laughed so hard that John Hughes said to me 'would you ad-lib a scene just as if you were teaching economics, and we'll see how it goes.

“He said 'don't write anything down, just [say] something that's really interesting to you, and I did the scene about tariffs and about voodoo economics, and the student extras applauded and laughed. I thought I'd taught them a good lesson about economics. They thought it was the most boring thing they'd ever heard.

“I was so happy, I called my wife on the way home and said 'this has been the happiest day of my life'. She said 'what about the day we got married?' So it was the second happiest day of my life. I'm sure when I die, they'll say 'media economist crank dies'.”

Read more: Spielberg on Goonies sequel

Indeed, Stein was a lawyer and then a speech writer for US presidents including Richard Nixon and Gerald Ford before he appeared on screen in John Hughes's 1986 teen classic (it was even speculated that he was the Nixon whistleblower known as Deep Throat for a time).

Post-Bueller, as well as becoming a law school professor, he became a conservative commentator, a comedian and gameshow host.

“He was a loving guy, and it comes across in the movies, and his movies are about love,” Stein added of director Hughes,” added Stein.

“They're not mean, they're not angry, they're not violent, thy are about love and they're about human beings connecting with each other on a level of love. And I don't see much of that anymore.

“You feel happy after you've seen Ferris. You feel happy after you've seen The Breakfast Club. You just feel better about life. My wife and I watch a great many movies, and we often say we feel suicidal after seeing [some of them]. With John Hughes, you feels there's purpose to life, and that life is a wonderful thing.”

Other revelations from the movie included the fact the the iconic Ferrari 250 GT was, in the main, a Ford with a Ferrari shell glued on the top of it.