When she was helping her son with his homework Saturday night, a Central Bucks mother noticed something that surprised and shocked her. "I couldn't understand what I was looking at," said the woman, whose identity the newspaper has agreed not to disclose. It was a work sheet called "Solving Equations using Multiplication and Division!" and it featured a photo of a black man wearing a straw hat, shirt and suspenders, with his mostly toothless mouth wide open. As if to underscore the man's stupidity, at the bottom of the picture was written, "No wai!!!" The mother learned that her son,...