Sharing is a developmental process that comes into actuality sometime between 2.5 and 3 years of age, provided that is the expectation and provided that the child has not been forced to share prematurely. In a Montessori community of children of mixed ages, all of the materials “belong to” all of the children and are available when no one else is using them, and a child has some information about how to use them.  New, young children coming into a Montessori environment usually have an older child that helps them understand the rules. For example, a child cannot take a material that someone else is already using, requiring the child to either choose something else to do or wait until the first child is finished with the material.  

Toddlers are infamously known for being selfish, saying “MINE” about most things. They are not selfish; they simply have not yet reached the developmental stage of being able to share.

When toddlers are forced to share prematurely, it often results in selfishness.