To label someone is to attach a "definition" to them. For example, teachers may label someone, thick, trouble maker, hardworking etc.
Howard Becker carried out study into labelling. It was based on interviews with 60 Chicago high school teachers, he found that they judged pupils according to how closely they fit the image of the "ideal pupil". Pupils work, and appearance of the pupil influenced teachers judgements. The teachers saw those from middle class backgrounds as the closest to ideal, and working class as further away from ideal because they regarded them as badly behaved.
Labelling can not just be applied to pupils, but also the knowledge they are taught. Gillborn and Youdell, shows how schools use teachers understanding of ability to decide which children have the potential to get more A* - C grades. They found working class and black children less likely to be percieved as having ability and more likely to enter lower sets therefore denying them extra knowledge which widens the class gap in achievement.
The self fulfilling prophecy
A self fulfilling prophecy is a prediction that comes true in this way:
1) teacher labels a pupil (very intelligent) and on the basis of this label, makes predictions about him (make outstanding progress)
2) teacher treats pupil accordingly acting like prediction is true (giving more attention)
3) pupil internalises the teachers expectation which becomes part of his self image thus becoming the kind of pupil teacher believed to be in the first place.
Rosenthal and Jacobson told a school they could identify which children would 'spurt' ahead. However all they done was a IQ test. The teachers believed it. researchers picked 20% at random and told the school they were spurters. A yeear later, they returned, and found almost half of those said as spurters had made significant progress.