Ms Atwell’s school in the rural town of Edgecomb, Maine, is no ordinary place of learning. Then again, Nancie Atwell is no ordinary teacher.

At her school, all classrooms have libraries, standardized tests are forbidden, classes are small, every religious and cultural holiday is celebrated, and students pick the topics they write about and the books they read. And read they do: her students wolf down about 40 books per year, well above the national average.

Earlier this month, Atwell was named the winner of a competition to find the world’s best teacher. She accepted the Global Teacher Prize, dubbed the Nobel Prize of teaching, at a ceremony in Dubai.

Atwell chose to dedicate the entire award – $1m worth – to the Center for Teaching and Learning (CTL), the nonprofit demonstration school she founded 25 years ago, which she said is in need of structural upgrades, including a new roof and furnaces, and many more books. “We will have a very healthy book-buying fund,” Atwell told the Guardian. “It’s the thing we never have enough of.”

Atwell’s prolific teaching career spans four decades and several school districts. She is also the author of nine books for teachers, including In the Middle, which sold half a million copies. Her goal, she said, is to make the classroom a place for “wisdom and happiness”, rather than one of stress and frustration.

The world’s top educator, however, said she never intended to become a teacher. Instead, she fell into the position while trying to figure out what to do with an English degree. After graduation, she took a student teaching position as a “fallback plan”.

“I fell in love with teaching,” she said. “I felt like I was home. I love literature and I really loved adolescents, I found out. And to have relationships with kids around books and to talk to kids about books seemed like the best gig in the world.”

She began teaching in western New York in 1973, starting out with a classroom full of seventh and eighth graders, her favorite grades. “When you hook seventh and eighth graders on something, I think you’ve hooked them for life,” Atwell said. “It’s such an important age in terms of kids establishing their world view and figuring out how the adult world works.”

But during these early years, Atwell realized students weren’t “hooked” on the books or writing prompts she assigned. She began researching alternative teaching methods and stumbled on the work of Donald Graves, a University of New Hampshire professor of early childhood education who is credited with pioneering the “Writing Workshop” teaching method that Atwell dedicated her career to improving.

Writing Workshop is a teaching framework that champions student choice and self-expression. In Atwell’s classroom, children choose their own books and writing topics, advance at their own pace and spend one-on-one time with teachers.

This discovery revolutionized her classroom. She immediately noticed student engagement increased when the children were allowed to choose what they wanted to read and write. “When I let go of my last bit of total control of everything in the classroom and let [the students] choose, they made wonderful choices, smart choices.”

While still working in the confines of the public school system, Atwell had no choice but to innovate without permission. “I closed the door of my classroom and talked to my kids,” she said. “I’ve found, consistently, kids know what’s interesting and what’s valuable if we let them have some say in it.”

After teaching in New York, Atwell moved to Maine, where in 1990 she founded CTL to experiment and share new ideas of teaching writing and reading. The school serves a maximum of 80 students from kindergarten through eighth grade.

At the school, teachers engage with students as fellow writers and readers, rather than the traditional instructor-pupil relationship. Each day the students spend time reading books they have chosen. They even curate a website of recommended books for other young readers. And Atwell makes a point of exposing them to as many cultures and traditions as possible during the school year.

“We celebrate the Chinese New Year, the Day of the Dead, the start of Lent, the end of Ramadan,” she said. “I want them to have a knowledge of and passion for the whole of society, and not just the tiny little slice they’re exposed to here in rural Maine.”

Every year teachers from across the country visit the school to observe the Writing Workshop method in action – and, Atwell hopes, integrate it into their own classrooms. The method has proven to work in diverse classrooms of students from all different cultures and socioeconomic backgrounds, she said.

The majority of her students excel in high school, and 97% matriculate to college or university. But when she looks at the nation’s vast public school system, with its rigid infrastructure and focus on standardized testing, Atwell said she sees a wholly detrimental shift toward uniformity in the classroom.

“Teachers are being essentially asked to be technicians, to read a script, and the script is not valid,” Atwell said. “[Test scores] are all that counts right now. It’s all data analysis, metrics and accountability. It’s a business model that has no business being applied to the craft of teaching or the science of learning.”

Atwell disagrees with the politically contentious common core educational standards, which she said focus too much on test scores, rather than lessons learned, or books read, as a mark of achievement. Students all learn at different paces and levels, and the common core standards steamrolls individuality and forces everyone to be quite literally on the same page, she said.

On receiving the award, Atwell said she was “gobsmacked”. She said the attention-grabbing prize is affirmation that the non-traditional teaching methods she has championed for more than four decades are not only valued and prized but are, more importantly, successful.

“I think the one thing we had in common, and it was really powerful to see this, was that none of us talked about test scores,” Atwell said. “We were talking about making meaningful changes in kids’ lives. I am so proud to be a part of a group of people who are professionals in every sense of the word. You just feel proud to be a teacher who was chosen to represent the profession.”

So what’s next for the world’s greatest teacher? Back to school, of course.