In the summer of 1962, Sledge was appointed Assistant Professor of Biology at Alabama College (now the University of Montevallo). In 1970, he became a professor, a position he held until his retirement in 1990. He taught zoology, ornithology, comparative vertebrate anatomy, and other courses during his long tenure there. Sledge was popular with his students, and organized field trips and collections around town. In 1989, he received an honorary degree and rank of colonel from Marion Military Institute.