Silly question, but highly curious. why do i do horribly on tests when encouraged despite my best efforts, but get straight a's when insulted? psych?

Unconscious response: You'd need to talk with a psychologist or psychiatrist to explore this fully. Our unconscious perceptions and thoughts dictate our behavior much more than our conscious ones do. You're clearly intelligent and able to perform on tests. So you'd want to explore what being encouraged means to you, in contrast to being insulted. Your inner relationship with the encourager or insulter is prime.