Montessori’s three period lesson is one of the most important teaching tools in the Montessori Method.

Finally there is the period of complete development in which the capacity to perform some operation is permanently acquired. There are, therefore, three periods: a first, subconscious one, when in the confused mind of the child, order produces itself by a mysterious inner impulse from out the midst of disorder, producing as an external result a completed act, which, however, being outside the field of consciousness, cannot be reproduced at will; a second, conscious period, when there is some action on the part of the will which is present during the process of the development and establishing of the acts; and a third period when the will can direct and cause the acts, thus answering the command from someone else.

When I used to take an exam in college, I found multiple choice tests much easier than essay-writing exams. Multiple choice is like the second period lesson where you point out the correct answer, whereas the essay requires the abstract knowledge of the third period lesson. The first period was always the college lecture-“a mysterious inner impluse from the midst of disorder”!