How do children learn math--and why do some children struggle with it? The answers are in "Number Sense and Number Nonsense," a straightforward, reader-friendly book for education professionals and an invaluable multidisciplinary resource for researchers. More than a first-ever research synthesis, this highly accessible book brings math difficulties into clear focus, helping educators and psychologists get inside students' heads so they can devise the best way to help children learn. Clinical psychologist Nancy Krasa and middle-school teacher Sara Shunkwiler combine their expertise for an eye-opening exploration of how the brain works during the many complex facets of math learning. Readers will gain a complete, research-based understanding of what it means when students struggle with: understanding relative values; comprehending spatial configurations; reading and writing numerals or other symbols; mastering arithmetic facts or algorithms; deciphering word problems or fractions; paying attention, tracking information, planning ahead, or thinking flexibly and critically; and reasoning abstractly and arguing logically. Educators will improve their math instruction with the classroom examples and helpful samples of student work, and psychologists will effectively evaluate math learning problems with the assessment guidelines and clinical case illustrations. With this in-depth guided tour of essential math skills and the difficulties students may encounter with each, education professionals will gain the insight they need to turn number nonsense into number sense for children who struggle with math. A bibliography and index are provided.