"You cannot pass an OWL," said Professor McGonagall grimly, "without serious application, practice and study. I see no reason why everybody in this class should not achieve an OWL in Transfiguration as long as they put in the work. So ... today we are starting Vanishing Spells. These are easier than Conjuring Spells, which you would not usually attempt until NEWT level, but they are still among the most difficult magic you will be tested on in your OWL."