NSTA Review: Why Do Cars Need Gas?

Yes, I review many children's books for NSTA.  Here's the latest.  My question is 'Why are these children's books so expensive?  $26.60?

Q&A Life's Mysteries Solved: Why Do Cars Need Gas And Other FAQs About Machines, by Amy Hayes, is an introduction to simple machines and early machine innovations, part of a series called Q&A Life's Mysteries Solved.  I like that the book immediately answers the question of why, exactly do cars need gas (pp. 4-5) before launching into a discussion of other machines, such as how an airplane flies (pp. 6-7).    This book poses a number of questions, 'How do skateboards turn?'(p. 12), 'Why do phones need to be charged?' (p. 16), and 'Who invented the vacuum?' (p. 22).  Did you know people once paid $4 a pop to have their house vacuumed? (p. 22). These are interesting questions for elementary aged children with clear answers.  Apart from being machines, the questions do seem a bit disparate.  But, I'm a sucker for interesting facts, such as the first electronic computer was built at the University of Pennsylvania (p.15) or that the first electric wind turbine was called the Brush Machine (p. 28). The diagrams, photos and explanations are appealing and will keep children turning the pages.  There's a glossary, index, and resource page (pp. 30-32) at the back.  Knowing how many children enjoy books with facts, this will make an excellent addition to any library.