Abuse indicates that the 'instructor' is overly defensive re his
ignorance.
From my limited observations of ninth grade science classes, reports from my
children on 5-9 sci classes and my own recollections, this response is
rampant in our public school systems.
My daughters flatly refused to let me teach them any physics. They clearly
stated their reason: they didn't want to know more than the teacher; it
would make her angry.