For more than five decades, Professor Emeritus Charles Krohn has nourished the soul of his students, teaching the classics at the University of St. Thomas in Houston — and he wasn’t about to let the coronavirus get in the way.

“They couldn’t run me off, so I just stayed around when the pandemic hit,” said Krohn.

But that’s meant embracing technology and a whole new way of teaching — at the age of 91.

When asked if his students are helping him, Krohn responded, “Oh, yes, definitely. Yeah, especially if something technical as well. ‘Well, Professor Krohn, why don’t you try this?'”

He currently teaches five days a week and often relies on his theater background to engage his students. 

“It makes for more communication because you’re aware of the audience, as I’ve now made, and in a way more aware of the students in this online contact,” said Krohn.

His dedication wasn’t lost on his former students, who took to social media after his virtual teaching went viral. One former student wrote he … “left a lasting impression on our lives.”

The father of four and grandfather of six has no plans to slow down anytime soon.

“You’re 91 years young, but I’m curious, how old do you feel?” CBS News asked.

“I don’t have a line, but like Jack Benny once said, ‘I feel … I. How old am I? Thirty-nine.'”