My daughter had problems with her chemistry and astronomy profs in school. I had her tape the classes, put on my battledress (active Army at the time) and "conveniently" ran into them at a market. I voiced my "displeasure" and advised them that if her grades suffered I would take "corrective" not "legal" action to resolve the issue. Never had a problem after that...with any of her profs. If parents don't get involved and find out what their kids are being taught (from Kindergarten on up!) they'll be paying the price later on.