A study in Australia found that over 600 incidents of improper parent behavior have been reported since 2008.
From the article:
"Public schools have made more than 600 reports since 2008 over improper parent behaviour.
Almost 240 incidents were reported to the Education Department last year, an increase of about 30 percent on 2008 when there were 180 incidents.
This has prompted Education Minister Jay Weatherill to ask the department to investigate ways of improving dispute resolution procedures for parents.
Family First MLC Robert Brokenshire has warned that the trend must be halted before our schools head the way of American schools and need security guards on every campus."
Read the rest here.