WorldlyWise Book 5 helps build vocabulary by including a wide variety of sentences with example words in them for students to get used to, according to Amazon. It also includes quizzes, games, and online components to support students.
The WorldlyWise series in general includes sentences with different levels of vocabulary for different grades. Book 5 is for 7-year-olds and up, according to the product description; however, the difficulty level does increase dramatically over earlier books in the series, according to individual Amazon reviews. The sentences contribute to this by detailing historical and social facts, including ones from fields such as art history, science history, and American politics. A younger child may have difficulty with some of these references or need them explained.
Book 5 does reflect other books in the series by including words that children are likely to run into in their school reading materials, says the EPS page describing the program. These are both fictional and nonfictional books, textbooks for all kinds of subjects and materials for standardized tests. Since the program is K-12, this explains the difficulty level growing over several books.
Parents who wish to check out specific content from Book 5 can visit the page for the book on the WorldlyWise website. This does not include all words from the book, but does offer word games, such as Hangman, and memory games, such as Concentration, that students may enjoy playing. Separate games are available for each set of four lessons.