BETHUNE, Helen . Why Do Glaciers Grind?: All About Extreme Environments ISBN 978-1-4488-0391-0 . LC 2009038269. BETHUNE, Helen . Why Do Monkeys Chatter?: All About Animals ISBN 978-1-4488-0394-1 . LC 2009038287. BETHUNE, Helen . Why Does My Heart Pump?: All About the Human Body ISBN 978-1-4488-0403-0 . LC 2009038260. BRASCH, Nicolas Why Do Shadows Lengthen?: All About Light ISBN 978-1-61531-891-9 . LC 2009034094. BRASCH, Nicolas . Why Do Spiders Live in Webs?: All About Animal Habitats ISBN 978-1-4488-0397-2 . LC 2009038285. BRASCH, Nicolas . Why Do Volcanoes Erupt?: All About Earth Science ISBN 978-1-4488-0400-9 . LC 2009038258. BRASCH, Nicolas . Why Does Sound Travel?: All About Sound ISBN 978-1-61531-888-9 . LC 2009031076. MCMAHON, Michael Why Do Stars Twinkle?: All About Space ISBN 978-1-61531-895-7 . LC 2009034097. MCMAHON, Michael . Why Does Thunder Clap?: All About Weather ISBN 978-1-4488-0406-1 . LC 2009038280. MOORE, Rob Why Does Water Evaporate?: All About Heat and Temperature ISBN 978-1-61531-892-6 . LC 2009034106. MOORE, Rob . Why Do Airplanes Fly?: All About Flight ISBN 978-1-61531-890-2 . LC 2009031078. MOORE, Rob . Why Do Balls Bounce?: All About Gravity ISBN 978-1-61531-889-6 . LC 2009024988. MOORE, Rob . Why Does Electricity Flow?: All About Electricity ISBN 978-1-61531-893-3 . LC 2009034101. ea vol: 24p. (Solving Science Mysteries Series). illus. photos. glossary. index. Web sites. CIP. Rosen/PowerKids Pr. Apr. 2010. PLB $21.25. Gr 4-6 The mismatch in this series between easy-to-read text and higher-level content may attract middle-school students who read below grade level. Volumes open with a dozen or so random questions and short answers on the chosen topic, followed by four pages of equally random facts, four thumbnail profiles of relevant scientists or inventors, a spread of word jumbles and other tests, and an easy activity. Surrounded by small color photos or diagrams, the text comes in short, digestible bits but contains occasional technical language, such as that in the discussion of Fahrenheit versus the Celsius and Kelvin scales in Water . Furthermore, Electricity assumes familiarity with parallel circuits. The scattershot topical coverage (the all about claim in each title is laughably false), along with rare but obvious factual errors (comets don't blow jets of matter toward the sun, as claimed in Stars Twinkle ) will make these titles of limited appeal.