The kids filed back into class Monday morning. They were very excited. Their weekend assignment was to sell something, then give a talk on productive salesmanship. Little Sally led off: ""I sold girl scout cookies and I made $30,"" she said proudly, ""My sales approach was to appeal to the customer's civil spirit and I credit that approach for my obvious success."" ""Very good,"" said the teacher. Little Jenny was next: ""I sold magazines,"" she said, ""I made $45 and I explained to everyone tha…