Harvey Hummel loved biology, but he loved teaching and inspiring high school students in the Robbinsdale School District even more.

His enthusiasm for both the subject matter and the 10th- and 11th-graders he taught through his rigorous Enriched Biology course for 27 years at Cooper High School and the former Robbinsdale High School made him a student favorite. He influenced hundreds of students to seek careers in the medical and science fields.

"His Enriched Biology classes were legend," said Peter Csathy, who took the class in 1980. "He taught with passion and vigor. It's not easy to make biology interesting, but he was deeply enthusiastic about opening the minds of his students. He was a high school teacher at another level."

Hummel died Sept. 6 of Parkinson's disease in an assisted-living facility in Dassel, Minn., where he had recently moved from Golden Valley. He was 89.

Born in Pennsylvania, Hummel developed an interest in classical and sacred choral music as a child. After high school, he was drawn to St. Olaf College in Northfield, Minn., because of its renowned choir. Though he never sang in any of the school's ensembles, he performed solo work on campus. He also was a wrestler, said his son, Chad Hummel, of Los Angeles.

Hummel graduated from St. Olaf in 1953, served in the Navy on the aircraft carrier the USS Valley Forge for three years and then earned a master's degree from the University of Michigan in 1959. He later earned a doctorate from the University of Minnesota and did postdoctoral work at Dartmouth College and the Harvard School of Public Health.

Hummel brought his enthusiasm for life, biology and teaching to Robbinsdale High in 1960. He created Enriched Biology, a course on par with today's Advanced Placement classes, his son said. He was known for jumping on desks with his pointer and shouting exotic-sounding biological names such as "Wuchereria bancrofti" (a parasitic worm) in his booming baritone voice. He was known for colorful expressions, too. When a student grasped a lesson, he would exclaim, "Now you're cooking with gas!"

"Students were enthralled with him," said Phyllis Kromer, a retired Robbinsdale High speech and English teacher who taught during Hummel's tenure. "He had enthusiasm for his subject and was very knowledgeable. It was not just facts about science. He looked at science in the broader context."

Mary Blue Helmbrecht, who is now the director of nursing at ComForCare Home Care in St. Paul, called Hummel a great biology teacher.

"The major reason I became an RN [registered nurse] was because of him," she said. "He made science fun. He made you want to learn."

Outside the classroom, Hummel was a lifelong learner. He was a voracious reader of fiction and nonfiction. His love for classical music never waned. Hummel amassed an extensive collection of records, and often played Mozart, Bach and Debussy in his home. He also loved movies and keeping up with current events, his son said.

Hummel was a member of Plymouth Congregational Church and was interested in world religions.

"He liked to go to any sort of lecture or church where those things were discussed," Kromer said. "He was a deep thinker."

Hummel is survived by his son; a sister, Lilian Griffin of Philadelphia; and three grandchildren.

His family donated his body to the University of Minnesota for Parkinson's research.

A celebration of life will be held at a later date.