The Montessori method of education is a system of education for children that seeks to develop natural interests and activities rather than use formal teaching methods. It was developed by physician Maria Montessori. It emphasizes independence and it views children as naturally eager for knowledge and capable of initiating learning in a sufficiently supportive and well-prepared learning environment. The underlying philosophy can be viewed as stemming from Unfoldment Theory. It discourages some conventional measures of achievement, such as grades and tests. Montessori developed her theories in the early 20th century through scientific experimentation with her students; the method has since been used in many parts of the world, in public and private schools alike.