"When it gets hard, you don't just give up."

Lowell Outland
Credit: Fayette County Public Schools/ABC News

Lowell Outland used to clean up after students at Tates Creek High School in Lexington, Kentucky. Now, the former custodian is a high school teacher at that same school, where these days he's only tasked with tidying up his own classroom.

On Wednesday, August 16, Outland returned to campus, greeting the students as their new graphic arts and digital photography instructor for the school year—a career change sparked, in part, by the students at Tates Creek.

"I got to know the kids, and there are some of them that are absolutely wonderful and I enjoyed being around them," Outland told ABC News. "I felt like it was time for me to start contributing a little bit."

The journey leading up to his advancement in higher education and a job promotion was a long one that was far from easy. According to Outland, it was an "overnight success that took 40 years."

Outland, a high school dropout, first earned his GED at the age of 23, while serving in the Air Force. Twelve years later, he got a job at a tire factory in Western Kentucky. When that company shut down, they offered to cover the expenses for Outland to go to Somerset Community College. He attained his associate's degree in 2007 at the age of 47 in electronics and industrial maintenance. Around the same time, he and his family moved to Lexington, and he began working for a local electronics company. After he was laid off a few years later, Outland went to work as a full-time custodian at Tates Creek in 2010.

It was there he decided to go back to school for his bachelor's degree.

Outland studied and took college classes in the morning at Morehead State University before his custodian shift started at night. It was a grueling schedule, but it eventually paid off. Not only did Outland receive his bachelor's degree in 2013 in technology and engineering, but he also received a teaching certificate, thanks to a program called Troops to Teachers that helps veterans.

"I think my past experience will give [students] something to think about," said Outland. "I'm showing them what they can do with their lives."

He was promoted this past July from custodian to teacher at the school he'd previously cleaned for seven years. A position that the school's principal, Marty Mills, was happy to promote him to, considering the good rapport Outland had already established with students.

"I'm just happy that we're able to keep him here," Mills said. "I just believe it's a great story for our kids and for everybody—that when it gets hard, you don't just give up."

Unperturbed by his age, the young-at-heart, newly-minted teacher, isn't fearful of beginning a new career at 59—an age when most people are retiring. Yet he had this to say when asked whether being around teenage students help to put a spring in his step: "Sometimes it does and sometimes it just wears me out."

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What a valuable lesson learned from Lowell Outland about perseverance. It reminds us all that it's not where you start, it's where you finish.