The Essential Montessori: An Introduction to the Woman, the Writings, the Method, and the Movement

First published in 1978 (then again in 1986 and 1997), this book is a classic. (It was one of the first books I read about Montessori education when I took my Montessori teacher training.) It explains all the basic aspects of Montessori education in easy to understand terms. Another popular aspect of this book is how Hainstock makes Maria Montessori's sometimes dense and challenging to understand writings more accessible. In fact, Hainstock is considered the first to "rewrite" Montessori philosophy and methodology to make it easier to comprehend. At only 127 pages long, you can read it very quickly.