You can argue but I think that we have two lives in our childhood and youth especially. First one is usual life. Is friendship and relationships. And the second one is school life. Often these two lifes across with each other. In school we find first real friends and someone even love. School has own atmosphere. Here's teachers and students. Here's we have long relationships with teachers. Usually they formal and we meet only in classes and don't know each other in first (real) life. Here's we get new knowledges every day and then get marks for them. This is system of school.