You will use this accounting stuff someday,” Larry Lease told his Shasta College students. “And if you become wealthy,” he would quip, “you can show your appreciation by buying me a Porsche.”

Happily for Lease, one of those students took the suggestion to heart. On Feb. 16, a decade after leaving the Redding, Calif., campus, multimillionaire software developer Robert Sullivan, 36, returned to visit a teacher who, he says simply, believed in him. Under the pretext of having forgotten something in his car, Sullivan lured Lease out to the campus parking lot. When they came to a spanking-new $51,000 Porsche convertible, Sullivan tossed him the keys. “It’s yours,” he announced. “You’re kidding!” Lease, 55, recalls saying as he backed away in shock from the 217-horsepower sports car. “I felt tears welling up,” he adds. “Then I started smiling, and I haven’t stopped since.”

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Sullivan’s gesture meant even more to Lease than his former student may have realized. In December 1995, Lease and his wife, Betty, 50, a newspaper editor, lost their 17-year-old son Adam to a car accident. Heart-broken, the once ebullient Lease cut back on his campus schedule to spend more time with daughter Amanda, 11, at the family’s five-acre Shasta, Calif., farmhouse. “The last several years have been very difficult,” says Betty. “When something so horrible happens out of the blue, it makes you that much happier when something so wonderful happens out of the blue.”

Sullivan, too, had waited years for his luck to change. The son of Bert Sullivan, a retired career Marine, and Danny Tweedy, a teacher’s aide at a preschool, the high school dropout left the Army before earning a general equivalency degree. He spent most of the 1980s working in fast-food joints in Redding. One bright spot was the accounting course he took with Lease at Shasta in 1986. Sullivan excelled, even becoming a tutor to other students. “Larry and I hit it off immediately,” he says. Still, friendship with an inspiring teacher wasn’t enough to keep Sullivan in school. He spent most of the next year living out of his jalopy. “I was eating cans of tuna, crackers, whatever I could afford,” he recalls.

By 1992, though, Sullivan had relocated to the Bay Area, taught himself computer software applications and become one of the first employees of what later became Commerce One, an online business-software company that went public last July, ballooning his net worth to nearly $40 million. More than enough to retire on—which is precisely what Sullivan did last October. But before moving to a six-bedroom Tudor-style home on 12 acres in Kentucky with his wife, Karen, 46, formerly a nurse, he had a delivery to make in Redding: one red Porsche. “I just figured it would be a killer gift that Larry could show his friends and have a lot of fun with,” says Sullivan. “It makes me feel good to do it.”

And it makes Lease proud to drive it. Ever generous, the teacher who used to get around in a 1996 minivan will let just about anyone who asks take the car for a spin. “It’s a little scary,” confesses Betty. “It’s small, powerful, new and expensive—but fun!”

Lease himself, who earns $65,000 a year teaching, might have had a high-flying corporate career. The son of an oil-supply company owner in Long Beach, Calif., Lease earned an M.B.A. from the California State University campus in his hometown in 1978 and then qualified as a CPA. But the former physical education and typing instructor realized that it was teaching he loved, so when he heard about an opening at Shasta, he went for it. Students return the respect. “At the Elks Club last year, a guy bought me a beer and said, ‘You were the best teacher I ever had,’ ” Lease recalls.

The recognition means the world to him. “They don’t have to buy you a Porsche—heck, they don’t even have to say you’re the best,” he says, “as long as they got something out of the class.”