While that may work in an "old school" system. My boss has shown me that the schools are no longer sending report cards through the mail. He can log on anytime he wishes and see all of his son's grades, test scores and homework assignment completions.
Now you need a talented h4x0r friend to adjust your grades before your parents log on.
Or some good old fashioned cheating before you get the grade. An once of prevention...
Good article though. Brings back memories of my youth.