In May 1954, Life magazine published a report on childhood illiteracy, which concluded that children were not learning to read because their books were boring. Accordingly, a director of Houghton Mifflin compiled a list of 348 words he felt were important for first-graders to recognize and asked Geisel to cut the list down to 250 words and write a book using only those words.
Nine months later, Geisel completed The Cat in the Hat, using 236 of the words given to him. It was imaginative with simple drawings and strong verse rhythms — but most of all, it could be read by beginning readers.
The Cat in the Hat and subsequent books written for young children achieved huge international success and they remain very popular today. In 2009, Green Eggs and Ham sold 540,366 copies, The Cat in the Hat sold 452,258 copies, and One Fish Two Fish Red Fish Blue Fish sold 409,068 copies — outselling the majority of newly published children's books.
Green Eggs and Ham
Green Eggs and Ham, written by Dr. Seuss, contains a vocabulary of only 50 different words, which is far less than the more chatty The Cat in the Hat, which uses 236 words. Here’s a word cloud (created by using Wordle) based on all the words in the text of Green Eggs and Ham.
Read Across America Day
Geisel's birthday, March 2, has been adopted as the annual date for National Read Across America Day, an initiative on reading created by the National Education Association.