Everything you need to understand or teach The Twenty-One Balloons by William Pène du Bois.
In this story, a sixty-six-year-old retired arithmetic teacher decides to take a hot-air balloon trip around the world in an effort to get away from everyone. Halfway around the globe, however, he becomes stranded on a volcanic island that is about to experience a massive eruption. The fantasy of The Twenty-One Balloons is built around an actual historic event—the massive volcanic eruption that destroyed the Pacific island of Krakatoa in 1883. But...