School is an opportunity that they often don't get any benefit from for any number of reasons such as their parents won't take them, buy them books or teach them how to behave. When they don't behave, teachers don't have time or in a lot of cases the authority to deal with the roots of the problems and just punish them by doing stuff like sending them out of class which lessens the benefit they would get from school and can also engender resentment from the kid which makes them more likely to act up and less likely to pay attention. And of course, there are also bad teachers. School is an opportunity but just because everyone gets schooling, doesn't mean they have had the opportunity to "make something of themselves."

You should think about changing your argument, I fully admit there are people in society who are given endless opportunity and so on but they're a tiny group of people and having a problem with taxation based on that alone doesn't make much sense, even if disliking them does make sense.