Here There Be Tygers (Skeleton Crew, #2)

Charles is a third grader. He really needs to go to the bathroom and his "mean" teacher Miss Bird asks him if he has to go before she allows him, embarrassing him. ("Very well Charles. You may go to the bathroom and urinate. Is that what you need to do? Urinate?") Arriving at the lavatory, he peeks around the corner, and sees a tiger lying on the bathroom floor. He stands at the door, too afraid to enter.