A unit on the study of ancestors sends Classroom 3B to sea when Ida, one of Harry’s classmates, reveals that her great-great-grandmother was one of the survivors of the sinking of the Titanic. Everyone wishes that they could sail aboard a big ship too, so Miss Mackle decides to take them on a riverboat trip. The whole class gears up by reading about all kinds of ships and even pirates. As they walk down the gangplank, each wearing his or her own personalized sailing hat, their spirits are not even dampened when they must sit on the lower deck. A bout of seasickness, a missing classmate, and even a rain shower keep the onboard action moving. Lively text and humorous drawings will entice even reluctant readers to call “All Aboard!” for this next volume in the Horrible Harry series. (Fiction. 7-9)