Twenty-five students gathered this fall in a University of Minnesota lecture hall when Max Arndt wandered up to a white board full of post-its and began to sketch a cube of sorts, to be bolted to the base of a door. It might be used in bathrooms, he explained, in dorms or bars or hospitals—anywhere one might not want to touch an often-gripped and likely germy door handle. The design was unclear—it just needed structural strength and the ability to be hooked by a human foot—and the illustration imperfect. But the name rang like crystal. Toepener.

The smirk-eliciting name came to Arndt one late night in his dorm room, when he was considering the mission of his class Entrepreneurship in Action: create as many ideas as possible, knowing that most of them will fail. And know that it's ideal to fail fast.

"I wanted to address a problem, but had learned it's OK to be out there with a possible solution, because it's okay to say 'this just isn't good,'" Arndt said. So, he used college dorm bathrooms as inspiration.

"I knew it was something of an annoyance to go to a public bathroom and touch the door handle. But there was no shock moment," he said. "This class gave me that moment to solve the problem."

Arndt came to class with his impromptu solution, and hasn't stopped talking about it since. That's because everyone in his class created possible ventures, pitched them to the class, and his idea made it through a series of eliminations, until his advisor signed off on a $15,000 loan to fund the Toepener's first manufacturing order.

About 100 Toepeners are in use in bathrooms across Minneapolis-St. Paul, and a few scattered around the rest of the country. After a spurt of news coverage, though, orders are piling up and Arndt's new venture—using unpaid help from the rest of his classmates—is racking up backorders. A shipment of 500 is underway, and the class is on track to repay its loan and be profit-positive by end of semester.

As for Arndt, who had applied to Business School as a restless high school junior upon his mother's advice, after graduation he plans to stay completely away from cubicle dwelling and start a company similarly geared toward Midwestern college life.

"I just know I want to do something involving beer," he said.