The biggest thing this biography has going for it is the undeniable appeal of its subject: John R. Horner, chief curator of paleontology at the University of Montana and scientific adviser to the film Jurassic Park (now there's a handy hook for getting young readers' attention). Horner is a ready-made kids' hero, with his gee-whiz way of speaking, his mediocre performance in school (he turns out to have been dyslexic), and his uncanny ability to spot dinosaur bones out in the field. Lessem (The Iceman, p. 702, etc.) presents some adult details of Horner's career in a way kids will understand. He flunked out of college seven times—a statistic that proves how persistent he was—but received an honorary doctorate anyway because he just knows so much about dinosaurs. Lessem also dramatically reveals Horner's major scientific discoveries: the first dinosaur eggs and embryos found in North America; the first evidence that dinosaurs nurtured their young; and the most complete T. Rex skeleton ever discovered. Lessem, founder of the Dinosaur Society for kids, has written a couple of books with Horner and obviously is a big fan of his, but the book works thanks to Lessem's own enthusiasm for dinosaurs and his impressive knack for writing in kid-speak. Getting kids interested in dinosaurs isn't hard, but giving them an inspiring scientist role model is no mean feat. This book pulls it off splendidly. (Nonfiction. 7-12)