Model Sherri Rawlings, 24, told reporters yesterday that she has a 'lingering feeling' that, for the past week, she has been standing naked in front of a junior high school civics class. 'At first, I didn't think anything of the fact that nobody had sketchbooks,' said Rawlings, who admitted that she had never attended a 6:45 p.m. 15th-period art class before this one. 'But when the banner written in big marker saying 'Advanced Human Portrait Drawing with Mr. Kimmel' fell, revealing a large Bill of Rights poster, I knew something was up.' Despite the unsettling suspicion, Rawlings said that she would continue posing at least until she was clear on the process by which a bill becomes a law. 