Chelsey Montgomery, Knellhart Academy

As a student at the University of Iowa, becoming a dog trainer was the furthest thing from Chelsey Montgomery’s mind.

“I was actually studying orthodontistry,” Ms. Montgomery said. “A complete 180, right?”

Dog trainers don’t necessarily have a typical career path. For Ms. Montgomery, the journey began when she purchased a German shepherd from a breeder in Georgia, who “took me under her wing” as an intern.

“I started training…