Although seemingly easy reading, picture books can still present a challenging independent reading experience to an age-appropriate reader for reasons of text difficulty and book layout or design.
Its Lexile measure of 740L, however, is around the average reading ability for someone ending fourth grade.
Additionally, picture books can have design elements that may visually complicate reading for a child.
Upon a closer look, the text comprises long sentences and contains some fairly high-level vocabulary such as "mischief," "private," "gnash," and "rumpus." The parent on the couch would help the preschooler sound these words out and decipher these long sentences.
Therefore the book is coded adult directed and the measure is AD740L.
Sometimes a Lexile measure by itself is not enough information to choose a particular book for a particular reader.
This is why some books get Lexile codes—two-letter designations that appear before the Lexile measure (for example, AD580L).