The Montessori method emerged in 1907 in a Rome slum and spread internationally within a decade. After waves of growth and decline through the 20th century, it experienced a major resurgence starting in the 1960s and now exists in over 100 countries with 60,000+ programs. Modern research has provided scientific validation, and public Montessori programs are expanding access globally.
The Montessori method is now over 115 years old. In that time, it has gone through three waves of explosive growth, one major decline, decades of quiet persistence, and a modern resurgence built on scientific research. To understand the method as it exists today, it helps to know how it got here.
This is the story of the method itself — how it was born, how it spread, why it nearly died, and how it became one of the most influential educational approaches in the world.
Before 1907: The Intellectual Foundations
The Montessori method did not emerge from nowhere. Maria Montessori built on a tradition of educators and physicians who had developed methods for working with children considered “uneducable.”
Jean Marc Gaspard Itard (1774-1838) was a French physician who worked with Victor of Aveyron, a feral child found in the woods. Itard developed sensorial training methods to teach Victor language and basic social behavior. His work demonstrated that even severely deprived children could learn with the right approach.
Edouard Seguin (1812-1880), Itard’s student, refined the approach into a coherent system for teaching children with cognitive disabilities. He developed many of the sensorial and motor materials that would later be adapted by Maria Montessori. His 1846 book Traitement Moral, Hygiène et Éducation des Idiots (Moral Treatment, Hygiene and Education of Idiots) was foundational, though the language and terminology are jarring by modern standards.
Maria Montessori, as a young physician in the 1890s, encountered Seguin’s work while studying children in psychiatric facilities. She traveled to France to study his methods firsthand, translating and adapting them. She also drew from contemporary thinkers in pediatrics, psychology, and pedagogy.
Her synthesis was original, but she always credited her predecessors. She was building on a tradition, not inventing from nothing.
1907: The Casa dei Bambini
On January 6, 1907, Maria Montessori opened the first Casa dei Bambini in the San Lorenzo district of Rome. The conditions were unremarkable: a small space in a low-income housing complex, fifty children ages 3-6, a single young woman as the daily teacher (Maria herself observed rather than directly teaching).
What happened over the following months was anything but unremarkable.
The children, many malnourished and from chaotic homes, transformed. They settled into long periods of concentrated work with the prepared materials. They learned to wash themselves and care for the room. By the spring of 1908, several were reading and writing at age 4 — a result so striking that observers initially doubted it.
Word spread. Educators began visiting. The Italian press wrote about the “miracle of San Lorenzo.” Maria began giving lectures and writing about her observations. In 1909 she published Il Metodo della Pedagogia Scientifica (later translated as The Montessori Method), the book that introduced her approach to the world.
By 1910, Montessori schools were opening across Italy. By 1911, in Germany and Switzerland. By 1912, in the United States. The method had become an international movement within five years of the first Casa dei Bambini.
1910s: First International Wave
The 1910s were the method’s first golden age. Schools opened across Europe and rapidly in the United States. Maria Montessori was an international celebrity. The first US Montessori conference was held in 1913 with thousands of attendees. President Wilson received her at the White House.
The American Montessori Education Association was founded in 1913 with significant institutional support. Schools opened in major cities. Anne George established the first American Montessori school in Tarrytown, New York, in 1911.
But this expansion happened against the backdrop of World War I (1914-1918), which disrupted European education and disrupted international exchange. Maria’s lecture tours were canceled or restricted. The energy of the movement was constrained by global crisis.
The war also produced new educational thinking, much of it influenced by figures like John Dewey in the United States, who emphasized progressive education with different principles than Montessori.
1920s: American Decline
The first wave of American Montessori crashed in the 1920s. The causes were several and reinforcing.
The Kilpatrick critique. In 1914, William Heard Kilpatrick, a leading progressive educator at Columbia Teachers College, published The Montessori System Examined. The book criticized the method on multiple grounds — that it was too narrow, that it underweighted imagination and social development, that its philosophical foundations were unsound. The critique was influential and shaped American educational discourse for decades.
Dewey’s progressivism. John Dewey’s progressive education movement offered a different vision of child-centered education, with more emphasis on social development, less on individual concentration, and a more democratic philosophical foundation. Many American educators who were sympathetic to child-centered education chose Dewey over Montessori.
Maria Montessori’s control. Maria insisted on personal control over teacher training and quality. This produced a small number of well-trained teachers but could not meet demand. American educators wanted to adapt and expand the method faster than her training could support. The friction grew.
The Roaring Twenties cultural shift. The 1920s brought new educational priorities — vocational training, standardization, mass schooling. Montessori, with its emphasis on individual development and slow concentration, fit less well with the era’s priorities.
By 1930, Montessori had largely disappeared from the American educational landscape. A few schools remained, but the method was widely seen as a curiosity of the 1910s.
1930s-1940s: Europe and Asia, War, Displacement
Outside the US, Montessori continued to develop. The Netherlands became a particular stronghold, with many schools and an active Montessori community. Italy continued to have schools (though Mussolini closed them in 1934). India saw early adoption.
Maria Montessori established AMI (Association Montessori Internationale) in 1929 to preserve the method internationally and coordinate teacher training. This organization continues today.
The 1930s and 1940s were dominated by political crisis. Maria left Italy after the fascist closure of her schools in 1934, settling first in Spain, then the Netherlands. World War II disrupted everything. Maria and her son Mario spent the war years interned in India, where she continued to train teachers and refine her approach.
The post-war period saw efforts to rebuild the movement. Maria returned to the Netherlands and continued working until her death in 1952. AMI continued to operate. But the method had lost momentum during the wars.
1950s-1960s: American Resurgence
The American resurgence began with one woman and one school.
Nancy McCormick Rambusch discovered Montessori while studying education in Italy in the 1950s. She trained at AMI and returned to the United States with a mission to revive the method. In 1958 she opened a Montessori school in Greenwich, Connecticut. The school was immediately successful and attracted attention.
In 1960, Rambusch founded the American Montessori Society (AMS). AMS was designed to adapt the method for American culture and to scale teacher training faster than AMI had been willing to do. The two organizations would have a complicated relationship for decades — sometimes cooperative, sometimes contentious — but together they would drive the American resurgence.
The 1960s saw rapid growth. Schools opened across the country. Teacher training expanded. The educational establishment, which had largely forgotten Montessori, took notice. By 1970, AMS had over 200 affiliated schools.
The cultural moment helped. The 1960s and 1970s were a period of educational experimentation in the US, with growing interest in alternatives to traditional schooling. Montessori found receptive parents and educators.
1970s-1990s: Public Montessori Emerges
The most significant development of the 1970s was the emergence of public Montessori. The first public Montessori program in the US opened in Cincinnati in 1973, as part of a magnet school strategy supporting voluntary desegregation. Other cities followed.
Public Montessori solved a major equity problem with the method. Private Montessori was expensive and accessible primarily to higher-income families. Public Montessori, free and open to all, expanded access dramatically. By 2000, there were over 200 public Montessori programs in the US. By 2020, over 500.
The 1980s and 1990s also saw international growth. Montessori spread further into Asia, Africa, and South America. The method took on new forms in different cultural contexts — adapted but recognizably the same method.
Maria Montessori’s children and grandchildren remained involved. Her son Mario led AMI until his death in 1982. Her granddaughter Renilde and her great-granddaughter Carolina continued the family’s work into the 21st century.
2000s-Today: The Research Era
The 2000s brought something the method had lacked in earlier waves: rigorous scientific research.
Lillard 2006. Angeline Lillard and Nicole Else-Quest published a study in Science comparing 5- and 12-year-old Montessori students to lottery-controlled peers. The Montessori students showed significantly better outcomes on multiple measures. The study was a landmark — it provided the first major peer-reviewed support for the method in a prestigious journal.
Lillard 2017. A follow-up study in Frontiers in Psychology tracked Montessori students over three years. The results confirmed and extended the earlier findings. Notably, the achievement gap between higher- and lower-income students was significantly smaller in Montessori than in comparison schools.
These studies (and others) gave the method scientific credibility that earlier generations had lacked. Researchers began studying Montessori with serious tools. Findings on executive function, intrinsic motivation, social cognition, and academic outcomes accumulated.
The research era continues. Studies on Montessori in diverse contexts, on long-term outcomes, on specific populations (children with special needs, gifted children, multilingual children), and on integration with modern educational technology are ongoing.
Where Montessori Stands Today
The method today has:
- Approximately 60,000+ programs worldwide, including 5,000+ in the United States
- Over 500 public Montessori programs in the US, with continued growth
- A solid research base documenting benefits in academic, social, and executive function domains
- Strong international presence, particularly in the Netherlands, India, Italy, the UK, and increasingly in countries across Africa and Asia
- Multiple credentialing bodies (AMI, AMS, IMC, and others) supporting teacher training
- An active home-schooling community practicing Montessori without formal schools
- A consumer culture of Montessori-aligned toys, materials, and parenting books reaching far beyond formal programs
Notable Montessori-educated public figures (Larry Page, Sergey Brin, Jeff Bezos, and many others) have brought visibility. Modern research has provided legitimacy. Public Montessori is expanding access. The method appears positioned for continued growth.
What the History Teaches
A few patterns emerge from this history.
The method works. Across waves of cultural and political change, in different countries and contexts, with different populations, the basic approach produces consistent results when implemented faithfully. This is not a fad.
Implementation matters. Each wave of decline has been associated with watered-down or poorly-implemented programs. Each wave of resurgence has been associated with renewed commitment to authentic practice. The method is not a brand. It is a coherent system that requires fidelity to work.
Cultural fit varies. Montessori has thrived in some cultures more than others. The Netherlands has embraced it more thoroughly than the UK. India has integrated it differently than the US. Cultural and political factors matter, but the underlying method translates across contexts.
Research helps. The current research era has done more for the method’s legitimacy than the previous several decades of advocacy. As more rigorous research accumulates, the method becomes harder to dismiss and easier to adopt at scale.
The original vision endures. What Maria Montessori observed in 1907 — that children given the right environment will learn far more than expected — remains the foundation. Everything else is implementation detail.
A Closing Thought
History suggests Montessori is here to stay. After 115 years and multiple cycles of growth and decline, the method has proven its durability. The research is now solid. The infrastructure (teacher training, accreditation, materials) is mature. Public Montessori is expanding access. New countries continue to adopt the method.
What started as a single school in a Rome slum has become a global educational movement reaching tens of millions of children. The story is not over. The next chapter — likely shaped by digital integration, expanded public access, and continuing research — will write itself in the coming decades.
For parents considering Montessori today, the history offers reassurance: this is not a passing trend. It is a method that has been refined over a century and continues to evolve. The fundamentals Maria observed in 1907 have proven both durable and adaptable. They are still doing the same work today, in classrooms around the world, that they did in San Lorenzo.
Children, when given the right environment, learn. That is the discovery. The method is the application. And the application keeps spreading because the discovery keeps proving true.
