<P> The concept of scaffolding can be observed in various life situations and arguably in the basis of how everyone learns . One does not (normally) begin knowing everything that there is to know about a subject . The basics must be learned first so one can build on prior knowledge towards mastery of a particular subject or skill . </P> <P> Various investigations, using different approaches and research frameworks have proved collaborative learning to be effective in many kinds of settings and contexts . Teachers should assign tasks that students cannot do on their own, but which they can do with assistance; they should provide just enough assistance so that students learn to complete the tasks independently and then provide an environment that enables students to do harder tasks than would otherwise be possible . Teachers can also allow students with more knowledge to assist students who need more assistance . Especially in the context of collaborative learning, group members who have higher levels of understanding can help the less advanced members learn within their zone of proximal development . In the context of adults, peers should challenge each other in order to support collaboration and success . </P>

As a child moves through a zone of proximal development (zpd) the teacher’s role is to