In 2008 when The TES published a series on "thinkers who have shaped modern education", Wendy Kopp was one of six figures deemed worthy of inclusion.
She made the grade alongside the likes of Howard Gardner, the famous Harvard professor who devised the theory of multiple intelligences.
Ms Kopp is not an expert on the brain or pedagogy. In fact the Texan is not a renowned academic at all. But aged just 21 she came up with one startlingly simple idea that is still reverberating around the world of education, reshaping it more than two decades later.
It was that if privileged, high-achieving graduates were recruited to teach in deprived communities with the same aggression as they were wooed by Wall Street, they would take up the challenge with enthusiasm.
Her optimism turned out to be well founded. It led her to set up Teach for America, which is transforming attitudes about education in disadvantaged areas, and in turn inspired its English cousin, Teach First.
On Tuesday Ms Kopp was at the City of London Academy, Southwark, to help mark Teach First Week - confusingly taking place next week - by teaching a class in a "challenging urban school".
Jaya Bawa, a Teach First recruit, usually teaches the Year 11 economics class Ms Kopp was allocated and warned that the 17 boys and just three girls could be really "scary" and "frightening".
"They are boisterous, they are loud and they love to show off," the 22-year-old Nottingham University graduate said. "But I'm sure Wendy Kopp will be OK - she's used to teaching in tough schools."
That had certainly been Ms Kopp's ambition when she was a liberal arts undergraduate at Princeton in the late 1980s.
"I felt like I was just searching for something I wasn't finding in terms of a way to make a real difference in the world," she remembers.
"The one thing I could think of that seemed inspiring was this idea of actually teaching in New York City in low-income communities."
She was convinced that many of her privileged Ivy League peers did not deserve to be labelled the "me generation" and shared her idealism. They just needed somewhere to channel it.
Ms Kopp wrote her thesis on the idea, concluding that she could get 500 of the most talented graduates into teaching, providing she had $2.5 million to make the scheme work.
Her professor told her the idea was "deranged". That was in 1989. Today Teach for America, which she founded a year later, places 7,300 teachers a year in 35 of the most deprived areas in the US and Ms Cope believes there is the potential for it to double in capacity.
In England, Teach First was set up in 2002 and is now an established part of the education system, delivering nearly 500 top graduates a year into schools in England.
Ms Kopp believes the secret of her success was naivety. "That was my greatest asset, my inexperience," she told the academy pupils.
"If you take nothing else from this 40 minutes, just think about that. There is a huge power in inexperience, in not knowing the way the world really works."
She told the teenagers how she had decided that Ross Perot, the billionaire businessman who ran for the White House twice in the 1990s, would be her best bet for finding the money she needed to start Teach for America.
Why? Purely because he had grown up in the same Texas town. "I had never met him," she said. "This is what you call completely naive. It makes no sense."
By the time she got to meet him, she had already selected 500 people for a scheme she still had no funding for.
"It was very embarrassing," she said. "I was about to die of stress. Before I got into his office I pictured myself glued to the chair in his office until he said yes. I was desperate and sometimes it is good to be desperate. I sat in that man's office for two hours and he said no 30 times."
Eventually, of course, he pledged the $500,000 Ms Kopp needed to kickstart her fundraising and she never looked back.
Whether the class Ms Kopp was teaching had any idea who Ross Perot is might be open to question. As is whether jargon like "true system level change" and "moving the needle" is the best language to use when teaching 15 and 16-year-olds from Bermondsey.
In fact, the class completely failed to live up to its ominous billing and was attentive, polite and asked very intelligent questions. But that didn't stop Ms Kopp from wondering afterwards whether she "lost them in there".
If she did, she could probably put it down to her lack of experience. Because, despite her early ambitions and most people's assumptions, the Teach for America founder has never actually taught. The instant success of her scheme meant that she never had the time. And that is unlikely to change in the future.
Today Ms Kopp splits her time between running Teach for America and being chief executive of Teach for All, an international umbrella group formed in 2007 to offer support for the growing number of countries adopting her model.
Schemes have started or are being developed in Australia, Estonia, Latvia, Argentina, Chile, Peru, Germany, India and the Lebanon; with potential for start-ups in another seven countries, including South Africa.
In fact it is only now, two decades on, that Ms Kopp's idea is really beginning to make its presence felt globally.
In England, the Conservatives, like Labour, have grabbed at it with both hands. A Tory government would further expand Teach First and create a Teach Now scheme for career changers.
Not everyone is happy about that. Critics fear that the emphasis on on-the-job training means that a generation is missing out on theeoretical knowledge that could make them better teachers.
Ms Kopp answers: " I think we have shown there are alternative paths." But she sees the supply of quality teachers as only a by-product of Teach for America and the schemes it has inspired.
There is a much wider, underlying "unifying mission" to infuse the whole of society with the desire to solve what she describes as "the problem".
The problem is the acceptance that economic disadvantage automatically leads to educational underachievement. She says her scheme is showing that with the right energy and commitment, that need not be the case.
Most importantly, it is demonstrating it to the cream of her country's graduates, many of whom will go on to lead in other fields.
Ms Kopp's real goal is to create a social movement for educational change. "These programmes really aren't teacher-quality initiatives per se," she explains. "The long-term idea of all these programmes is to build a force of leaders at every level of the education system and every level of policy across professional sectors."
She is already well on her way. Two Teach for America alumni are members of Barack Obama's education team, another runs Washington DC's schools system, and two more have set up the Kipp charter schools, a rapidly expanding programme that is challenging the notion of what can be achieved in low-income communities across America.
None of this surprises Ms Kopp: "When you teach successfully in a disadvantaged community you learn through your first-hand experience that we can solve the problem.
"You learn that when kids are given the chances they deserve, they excel. I think it is really impossible to leave this once you realise that."
WENDY KOPP'S CV
Born: June 29, 1967
Education: 1989 graduates from Woodrow Wilson School of Public and International Affairs, Princeton University, with a BA
1990: founds Teach for America
2008: named one of Time magazine's 100 most influential people
Family: Lives in New York with husband Richard Barth - chief executive of the Kipp foundation which trains leaders for Kipp charter schools - and their four children.