At first glance the title might seem a bit odd, it may seem the opposite of what we want to achieve and it is. This may be a greater issue than we think. Normally a student which can't do something may ask for help from a peer or a more capable peer. Or in the case of a question, the student who doesn't know the answer may take a while to process something to answer. As Sir Ken Robinson said in his speech 'If children don't know, then they'll have a go.'
If a student can't answer right away, it is our jobs as teachers to allow the process time to naturally occur or to evaluate the interaction occurring and perhaps elicit from another student. But not to provide the answer.
Why do so many teachers answer their own question for the students? This gets into the whole issue of display questions and referential questions, but I've seen many teachers as a student a question only to answer it for them a few seconds later, not even waiting for that process time to occur.
What we need to do, is help students discover their own ZPD, discover their abilities and in doing so narrow their ZPD's to the point where the student can incrementally process his or her own abilities and discover their own limits. By knowing their own abilities they will be more likely to be autonomous learners and be able to stretch their imaginations and gain confidence in whatever they do. They will be able to challenge anything. We will have taught them that they can.
This silence is necessary for students to work out an answer, so why do teachers intervene and answer for them to spur the class along? It doesn't do any good for the student and it teachers them two things.
The students who wait for the answer, don't learn to think and never discover their abilities. They are too busy avoiding them.
The students who need more time to process learn that they can't answer and despite the fact that they may really know the answer, may end up just giving up because their journey through their 'self' ZPD was interrupted.
I don't think this is what Vygotsky had in mind in his ZPD theory.
Students who may know the answer but are told the answer before the processing is finished learn a very great bad thing.
They learn that getting help from a more capable peer means that the answer is provided whether they want it or not. They learn that their abilities are limited and someone thinks that their ZPD is too wide to be able to process on their own. They learn that there is a teacher who they hold in high regard doesn't think they have ability. The ZPD is not just a concept, it is our responsibility to help students learn to process their way through it through scaffolding and through collaborative efforts. The ZPD is I think, directly linked to self worth and self recognition.
So for teachers who don't pause, who don't wait for that process time to occur are not helping. We need to challenge our students and help our students really discover their own abilities. Not provide the answers because we want to hurry the class along.