Education in the schools is important, but parents also have to be educated. Young people have an easier time using the computer than their parents. In fact, the parents often ask the kids how to surf the Internet.
There are a number of ways of going about it, as some arrangements show. It's not a cure-all, but one way is to take the computer out of the young person's bedroom and set it up in the living room, for example, or in another room that is accessible to everyone, so that the child is not isolated. It is when the child is isolated that he or she starts visiting sites that should perhaps not be visited. That way, an adult can always watch what the child is doing.