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Montessori in the United States

In 1911 and 1912, Montessori's work was popular and widely publicized in the US, especially in a series of articles in McClure's Magazine. The first North American Montessori school was opened in October 1911, in Tarrytown, New York. The inventor Alexander Graham Bell and his wife became proponents of the method and a second school was opened in their Canadian home. The Montessori Method sold quickly through six editions. The first International Training Course in Rome in 1913 was sponsored by the American Montessori Committee, and 67 of the 83 students were from the US. By 1913 there were more than 100 Montessori schools in the country. Montessori traveled to the United States in December 1913 on a three-week lecture tour which included films of her European classrooms, meeting with large, enthusiastic crowds wherever she traveled.

Montessori returned to the US in 1915, sponsored by the National Education Association, to demonstrate her work at the Panama–Pacific International Exposition in San Francisco, California, and to give a third international training course. A glass-walled classroom was installed at the Exposition, and thousands of observers came to see a class of 21 students. Montessori's father died in November 1915, and she returned to Italy.

Although Montessori and her educational approach were popular in the US, she was not without opposition and controversy. Influential progressive educator William Heard Kilpatrick, a follower of American philosopher and educational reformer John Dewey, wrote a dismissive and critical book titled The Montessori Method Examined, which had a broad impact. The National Kindergarten Association was critical as well. Critics charged that Montessori's method was outdated, overly rigid, overly reliant on sense-training, and left too little scope for imagination, social interaction, and play. In addition, Montessori's insistence on tight control over the elaboration of her method, the training of teachers, the production and use of materials, and the establishment of schools became a source of conflict and controversy. After she left in 1915, the Montessori movement in the US fragmented, and Montessori education was a negligible factor in education in the US until 1952.