Basically, to answer your title question, whatever the state wants to call abusive.
I disagree. This article, all though most have focused on the CPS part, is directed squarely at the parents. What is abuse in their eyes and do they investigate their processes enough to recognise the lines or, is it all about their own convenience and beliefs without regard for the child?
I agree, school and education are very, very different and even though my daughter will likelygo to school, that is not where she is going to be educated.