Scaffolding is an extremely social form of instruction. It is an important instructional tool because it supports student's learning. Scaffolding occurs in learning situations where the learners have opportunities to communicate their thoughts. Instructional scaffolding lies at the heart of the verbal interactions that induct students into the practices of the academic discipline. To implement scaffolding successfully, teachers first determine the difference between what each student can accomplish independently and what she or he can accomplish with guidance - the student's zone of proximal development. Then they provide instruction with just enough support for the students to participate in tasks that would be beyond their reach without teacher support. Levels of support in scaffolding vary widely. Several types of scaffolding that occur during learning conversations are also presented.