Education, society, families, all this has changed since the times when we sat in rows, listened quietly and did what we were told.  Teaching is a much different job than it was even 30 years ago.  Parents of higher achieving students are much more involved, while others lead extremely dysfunctional lives, so teachers are more and more de facto counsellors dealing with chronic absenteeism, mental health issues and a wide variety of special needs.  Add to that the increased paper work and obvious anti-teacher rhetoric you see on posts such as this, and you can see why 50% of first year teachers leave the profession.