Most college graduates earn their degrees in their early 20s, but one scholar recently walked across the stage at age 90.

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Bob Dwyer received his bachelor's degree in interdisciplinary studies from Northeastern Illinois University on Monday, making him the school's oldest graduate, according to ABC 7 Chicago.

In the 1940s, he dropped out of college to enlist in the Army. After he left the service, he enjoyed a career in the fastener industry, which allowed him to travel all over the world.

“At the time I left school, in my mind, it was a temporary thing. But time passed on and an opportunity never really was right for me to go back,” he told the news station.

After he retired, he decided it was time to go back to school. Over the course of two years, he took philosophy, sociology, communications, geography, education and political science classes to finish his interdisciplinary studies degree.

And he admitted it was hard.

“It's a little bit harder than you might think, but so what? As they say, when the going gets tough, the tough get going,” he said.

Many of his supporters, including his nine children and most of his 22 grandchildren, attended his graduation ceremony.

He said he hopes his journey will inspire others to follow their dreams despite the roadblocks.

“It’s never going to be too late,” he said. “I think the reward is worth it.”

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