I created a whole curriculum around this book, teaching my 4th graders to use the library to find books explaining Krakatoa, volcanos, and world geography. We took turns reading "21" out loud and made vocabulary lists to look up in the dictionary. The kids loved all of it. The only way I found the book to have not aged well is the use of "Negro" at one point. So we talked about that, and what the word meant, and means, and I gave them the idea that people deserve to be called what they want to be called.

Somewhat later, I studied up on early gas supplies in ballooning, and became a little disillusioned with the original balloon's ability to stay afloat. Creating hydrogen on the spot involved trucking around iron filings and hydrochloric acid. I don't recall this in Prof. Sherman's wicker house.

K.