Riddikulus!

Source: merlinsfuckingbeard.tumblr.com

Apparently, Parvati did not understand the point of this assignment. Also, she apparently doesn't realize that the spell 'riddikulus' clearly refers to the word 'ridiculous' implying that you make a mockery out of the thing you're afraid of, or cause it to be humorous. I don't know about everyone else, but that giant scary-ass clown does not seem to do wot was implied. I'm going to go ahead and call her an idiot.