Maria Montessori was Italy's first female doctor. She started a school for disadvantage children in Rome at the age of 28 and over the following two years, through experiment and creative thought, she developed educational techniques that really worked. After further education in anthropology and psychology, she took charge of a school for children living in a Roman slum. Her results became known worldwide and she was asked to set up a classroom behind glass at the 1918 Internaional Exposition in San Francisco.
Montessori techniques are popular with homeschoolers because they do not require a rigid classroom environment. http://www.tutoringforsuccess.com/montessori.html
Her works have been translated into English.
Read more on the Montessori Method in Wikipedia: http://en.wikipedia.org/wiki/Montessori