Growing up, Henry Winkler thought he was stupid. Beginning in ninth grade, he took the same geometry course for four years, repeating it over and over during the regular school year and again during summer school.

He finally passed with a D- the summer after his senior year. He’d already missed walking at his graduation, and he received his high school diploma in the mail. Winkler’s parents, who emigrated from Germany on the brink of World War II, were generally unsympathetic to his plight.

“At 31, I found out I wasn’t stupid, I wasn’t lazy,” he said. “ . . . I had something with a name. I had dyslexia.”

But by no means does “dyslexic” define Winkler. He has gone by many other labels, too — actor, producer, director, author, Fonzie.

“I didn’t need my parents to be proud of me when I figured out how to be successful,” he said. “I needed them to be supportive of me when I was confused, when I couldn’t figure out what was going on.”

Speaking to a crowd in the Oakland Center Banquet Rooms on Feb. 13, Winkler shared his life story, emphasizing his childhood struggles with learning challenges, which he has used as inspiration to write the Hank Zipzer children’s book series.

Like his creator, Hank has dyslexia.

“His glass is half-full,” Winkler said of the character. “He just spills it everywhere.”

Some of Winkler’s favorite (and least-favorite) teachers have made it into the books, as well. During his lecture, he showed the audience a photo of his music teacher, Mr. Rock.

“Mr. Rock was the only one who said, ‘Winkler, if you ever do get out of here, you’re going to be OK,’” Winkler recalled. “I held on to that one sentence like Leo DiCaprio held on to that piece of wood.”

Nowadays, Winkler portrays Mr. Rock on the BBC’s television adaptation of the Hank Zipzer series.

“I get to play Mr. Rock,” Winkler said enthusiastically. “I get to tell Hank Zipzer in the TV show, ‘You are more than you can imagine you are.’”

Thirty-three years after “Happy Days” ended its 11-season run, he still looks back fondly at his time as The Fonz.

He told the story of an ABC mandate that Fonzie could only wear his leather jacket when he was near his motorcycle, created out of fear that the character would be associated with criminal activity. From that point forward, the show’s creator Garry Marshall made sure that Fonzie had his motorcycle with him at all times.

Winkler said he used to receive 50,000 pieces of fan mail every week.

“Girls would chew gum, and they would take the wrappers, and they would make a daisy chain out of the wrappers,” he said. “And the bigger the ball, the more they loved me. There must be women all over this country with no teeth.”

Though he worked humor and anecdotes from various stages of his life into the lecture, Winkler circled back to one overarching message: acceptance and support for all children.

“Our job is to make sure that every child we know, whether they’re related to us or not, we make sure they meet their destiny,” he said. “We make sure they meet what they were put on this earth for.”

After the lecture, Winkler answered questions from the audience and held a meet-and-greet. He sold and autographed copies of his 2011 book “I’ve Never Met an Idiot on the River,” which includes lessons and photos from his time fly fishing in Montana.

Winkler’s lecture was hosted by the Student Life Lecture Board and sponsored by OU’s Disability Support Services, School of Education and Human Services, social work program and Division of Student Affairs.