ARTHUR'S MYSTERY ENVELOPE - What can possibly be in the sealed envelope Mr. Ratburn sent home with Arthur? Arthur is so worried he can't even eat or sleep. Whatever it is he's done, he's sure it can't be good. ARTHUR MAKES THE TEAM - It feels as if it's going to be a long season for Arthur as he struggles to sharpen his baseball skills. But before it's all over, he learns an important lesson about teamwork. ARTHUR ACCUSED! Arthur's heart is in the right place when he collects quarters to buy a new Dalmatian for the fire house. But when he is accused of stealing the money, Buster must come to the rescue and solve the mystery. ARTHUR AND THE LOST DIARY - Sue Ellen confides everything to her diary. So when she loses it in the library, the hunt is on.