It is Halloween morning. Arthur is dressed up as a ghost for the school party. Then he spills ketchup on his costume, and that's just the beginning. Now Arthur has a crazy costume that nobody can figure out- until Wilma's big sister comes up with the most original idea.

When Violet has a numbers problem and Arthur is penniless, they go into business and solve both problems.

While hurrying to get on the school bus, Arthur and his friend unknowingly switch their lunch boxes; later Arthur finds out what surprise his sister had put into hers.

Bored with spring vacation, Arthur decides to go alone on an overnight field trip in the woods behind his house.

Silly Tilly Mole is so forgetful and silly on Easter morning that she cannot find her bonnet and nearly fails to let the Easter Bunny into her house.

After they have a falling out, Arthur and his best friend Norman make up with very special valentines.