The child begins to perceive the world not only through his [or her] eyes but also through his [or her] speech

Thought is not merely expressed in words, it comes into existence through them

The distance between the actual developmental level as determined by independent problem solving and the level of potential development as determined through problem solving under adult guidance or in collaboration with more capable peers

What children can do with the assistance of others might be in some sense even more indicative of their mental development than what they can do alone

A child’s greatest achievements are possible in play, achievements that tomorrow will become her basic level of real action.

Learning is more than the acquisition of the ability to think; it is the acquisition of many specialized abilities for thinking about a variety of things.

A word devoid of thought is a dead thing, and a thought unembodied in words remains a shadow.