Aaah don't worry, Easy, it probably won't be your ds who causes difficulty in the classes. We teachers can usually pinpoint the ones who are going to be trouble within a week of starting school.
Martinbishop is so much more elequent than me on the subject, but as far as I can tell, it's about consequences. I work in FE, and by the time students attend college they are post 16, therefore it is not beholden on us as a educational institution to keep the students on(though there are consequences in terms of funding, but that's a whole other subject). When children are under 16, the govt have made it almost impossible for a school to permanantly exclude them. So children have learnt that they can behave as outrageously as they like because, in the end, there are no real consequences for bad behaviour. Essentially they have learnt that there are no consequences for poor behaviour in school.
Imagine how those students who don't really have to deal with consequences for poor behaviour at home feel when they hit college and encounter the dragon from hell (i.e. me )who expects them to turn up to class on time, expects them to do their work expects homework to be completed and handed in, expects respectful behaviour both towards the teacher and each other, expects, in short, simple common manners. The poor dears have a great deal of diffculty in coping. Inevitably we get some who can't deal with the idea that it is simply not OK to shout over the teacher, do no work, play around with equipment, have mobile phone conversations in class and drop out. What is interesting is we tend to see these students 3 or 4 years later as adult students. What happens is they cannot cope with some simple self discipline, leave college, try and get a job, get fired for turning up late and swearing at the boss, spend 4 years or so growing up then come back to finish their education.
The students who have learnt from their parents that actions have consequences are usually the ones who thrive after the initial adjustment period.
Of course, you could always go down the 'blame Maggie Thatcher' route too. My students, maybe more than most, see personal success in terms of income. They know teachers are poorly paid, therefore, in their eyes, we are a bunch of failures who don't deserve any respect. The only ones in the class who deserve respect are those with the flashest mobile phones, the fastest cars and the most extensive designer wardrobe. How can we compete with that mindset???