Hide behind Dumbledore
From Create Your Own Story
DumbleDore steps aside and frowns at you. "Are you sure you should stay here, Potter? I'm really considering sending you home...and I don't send students home often here...but you are not the Potter you once were. Don't you remember anything?"
After a while of thinking about this, Dumbledore turns to you. "Potter follow me please, I need to show you something." He walks up the long staircase and into a room full of moving pictures. There are pictures of you... as an infant... with yourparents his real parents! Dumbledore stares at you and waits for you to remember something...anything.
Remember but lie and say you don't and should get home. That he must be sick, you are not a wizard
Look up at him and shout with excitement that you remember it all so well now.