Well, iman0493, I have been teaching for more than twenty years and I believe in the truth of the old saying, "The Devil makes work for idle hands." The Danish existentialist philosopher Soren Kiekegaard, whose name I have most probably mispelled, put it slightly differently: "In a child's imagination lies everything we call the life of the mind." In other words, schools ought to provide their students with a wide variety of challenges: practical, intellectual, artistic, sporting, musical and so on. Children who are bored are bound to get into mischief sooner or later.