Art was Robert Paul's passion; teaching was his life. He merged the two as a reserve teacher at Minnetonka High School.

But as a reserve teacher for 20 years, he was just as likely to teach AP calculus, history or English. And for thousands of Minnetonka High School students, Paul became known as the "Trusty Reserve."

"It was his life," said his wife, Lizz. He quit teaching only when health issues sidelined him last fall, shortly after he turned 80 years old, she said.

On Tuesday, Paul died of natural causes in his Minnetonka home.

Growing up in South Dakota, Paul began teaching in Sioux Falls, S.D.

The Army put his career on hold while he served in Korea from 1951 to 1953. Once back in the United States, Paul earned his graduate degree from the University of Iowa and began work on a doctorate.

But as a father of one young child and with another on the way, Paul took his professor's advice to get out into the field and teach. He never looked back, his wife said.

Paul taught junior high school for seven years in Newton, Iowa, before moving to Minnetonka in 1964 to develop and coordinate a K-12 program to help teachers bring art into the classroom.

"Most teachers were intimidated and didn't offer art, at least nothing more than crayon art," Lizz Paul said.

Paul later was hired by the Minnesota Department of Education to help introduce art in elementary classrooms throughout the state.

"He spent a lot of time teaching young teachers how to teach art and how to captivate and motivate [students]," said his daughter Beth Norton of Grand Forks, N.D.

When state financing for the program ended a decade later, Paul worked as a graphic arts designer and taught private art classes.

He also served as academic dean of the Minneapolis College of Art and Design in 1968, following four years as the director of the Minneapolis Institute of Art's Saturday Gallery Club for young art students.

As a reserve teacher at Minnetonka High School, Paul easily won the hearts of the students.

"He was a student favorite," said Minnetonka High School psychology teacher, Polly Patrick. "He was so respectful of the students, besides being a lot of fun. ... He always engaged them in conversation and let them know he cared."

When he walked down the school hall, students wanted to stop to talk with him, she said. He was interested in them and then remembered what was important to them, Patrick said.

"He was the kind of genuine person you want around kids," she said.

Kids of all ages were always drawn to him, his daughter said. "He would be standing in line at Target, and a little boy would be looking up at him. So my dad would take out his handkerchief."

Making a few folds, Paul transformed the handkerchief into Mortimer the Mouse. "The mouse would come alive. Dad would giggle, and the kids would be filled with delight," Norton said. "He had magic with children."

In addition to his wife and daughter, Paul is survived by another daughter, Linda Buettner of Minnetonka; two sons, Matthew of Bloomington and Thaddeus of Bellevue, Wash.; three grandchildren; his brother Bill of Hobe Sound, Fla., and his sister Susan Deter of Sun City, Ariz.

Services will begin at 10 a.m. today at First Memorial Funeral Chapel in Edina.

Mary Lynn Smith • 612-673-4788