Maria Montessori observed and studied closely the traits of sensitive period with children within her framework.The sensitive period are refer to as windows of opportunities or
developmental milestones in other pedagogies.
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This is a time in a child’s life when a certain skills shows forth strongly. At these stage a child has really strong sensitivity towards a particular ability or knowledge. It is a period or time where a child concentrates mostly on one aspect of his environment and forget about every other thing.

 A child is seen doing a particular activity repeatedly with keen interest and determination in his/her eyes and it looks as though nothing can hinder them from accomplishment. This is a time of extreme concentration and mental activity on developing an ability at that period of time, age and phase.

It is an unconscious drive by an inner force and this is the appropriate time a parent can support her child by preparing the environment and encourage this special learning period.
Parents and teachers needs to observe and take advantage of these period of sensitivity as it doesn't lasts forever, neither does not it re occur.

The sensitive period can be used to determine the child readiness to learn and so on.

“The child has a creative aptitude, a potential energy that will enable it to build up a mental world from the world about it. He makes numerous acquisitions during the sensitive periods, which put him in relation to the other world in an exceptionally intense manner.” Maria Montessori "The Secret of Childhood"

Sensitive Period From Birth to Six years.
From birth (infancy) to six (childhood) years old is the sensitivity period for the following;

1. Birth to one year: Movement 
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