An Ethics question for Y'all

So, if they were sending grades out by mail like last year, I wouldn't know how I did until after we returned from gallivanting around wherever. Does that mean I don't have to check my email until after we return home, or at least not tell my parents how I did until they would have learned this time last year?

Or, how about pretending I took fewer hours and just leaving out the other grades? I’m not expecting Cs or anything, but you never know how stats may find a way to screw me over in the end. It certainly tried hard enough during November.