Paul, that's funny, I had the same things happen to me. I think the poor teachers were just trying to include me in on something so I wouldn't be left out. And to my little child brain it made perfect sense, I mean what's really wrong with coloring a tree (for instance)? Of course, we know the answer is 'nothing' but I usually got reamed for those 'infractions' anyway ...
Ah the wonderful childhood memories of dub-dom.