You don't find Avi's books too preachy? My kid had to read Charlotte Doyle last summer, and while he read his way through 5 Pendragon books and the last two Percy Jackson in a month, I could barely get him to finish that book at the same time. And his two best friends had the same response. It might be boys, though. But there was another one of his they had to read, and it seemed similarly didactic?