Skinny Nora Jean Sampson and her friends at R.B. Nolen Elementary School are kept busy with a snake in the girls' bathroom, a scary Halloween fun house, and a pizza party in the library.

In 1888, Owney, a stray terrier puppy, finds a home in the Albany, New York, post office and becomes its official mascot as he rides the mail train through the Adirondacks and beyond, criss-crossing the United States, into Canada and Mexico, and eventually traveling around the world by mail boat in 132 days.