Zzz, the fourth book in Kids Can’s Mysterious You series, lives up to its lengthy title. Its brightly coloured pages, packed with ample illustrations and sidebars, make this book an attention-grabber, and its wide-ranging text will keep that attention. Zzz provides a thorough introduction to the science of sleep, with two-page discussions on topics including sleep cycles, dreams, disorders, and napping. Kids will enjoy the quirky facts as well as the solid information, and parents will certainly appreciate the text’s message about getting enough rest. Its format and introductory style make it more likely to appeal to readers aged 9 to12 than to the suggested range of 9 to 14.

Trudee Romanek, author of The Technology Book for Girls and Other Advanced Beings, presents information clearly without dumbing it down for her readers. She uses scientific terms throughout, providing concise definitions and phonetic pronunciations. While vocabulary such as “suprachiasmatic nuclei” does make this book a more challenging read, it also shows respect for children’s intelligence and curiosity. Anecdotes in sidebars accompany the more scientific discussion for each subject, thereby accommodating a variety of reading levels, and a logically ordered index helps readers browse. Victoria artist Rose Cowles’ illustrations and diagrams add levity and clarification, and Romanek also suggests several “You Try It” experiments. While these activities, such as watching a sleeping person’s (or pet’s) eyeball movements, are a bit thin, they do provide readers with some safe learning applications.