It is hard to describe What is Montessori in a short paragraph. The philosophy allows the child to make his own choices, exercise courtesy, be responsible and enjoy learning - but how? It is best if you can visit a Montessori school nearby, and take notes of the children's activities. You will notice a buzzing-humming  sound of active children. Each of them may be engaged with a friend or on their own with a different unique materials.

What is Montessori in 100 words:

"As a scientist, Maria Montessori discovered something surprising:
When children are active participants,
when their choices are respected and guided, and
when responsibility is expected and nurtured,
a new child emerges.
This child’s characteristics are concentration, self-discipline, love of learning and a respect for others and the world.
This child is our best hope for the future.
Share the hope.  Experience the surprise.

Visit a Montessori school today."

By Peter Davidson. Chairman MAA, Board member AMI. Head of School.

"Montessori is a brain-based developmental education method that allows children to make creative choices in how they discover the people, places and knowledge of the world.  It emphasizes hands-on learning, self-expression and collaborative play in a beautifully crafted environment of respect, peace and joy."
Steven Hughes, Ph.D, L.P, pediatric neuropsychologist, Assistant Professor of Pediatrics & Neurology, University of Minnesota Medical School. American Board of Pediatric Neuropsychology.

One of the most reliable sources of information about "What is Montessori?" can be found on NAMTA , The North American Montessori Teachers' Association,  a membership organization open to parents, teachers, and anyone else interested in Montessori education. One of the more interesting reading is the section about Common Misconceptions about Montessori Education.

Look at the Frequently Asked Questions on the left for more info.